Re: [Rd] make check-all fails (PR#7784)
M. Edward (Ed) Borasky [EMAIL PROTECTED] writes: [EMAIL PROTECTED] wrote: This looks more serious. 100 times machine precision is quite a large margin in these matters. Could you perhaps stick in a printout of the two terms and their difference? I have an ATLAS build on AMD64 and it passes all the checks, but it is using ATLAS 3.7.8, so you might want to try an upgrade. Attached ... you actually weren't very far off: ... print (f2[common]) 1 2 3 4 7 8 9 32.971099 37.113091 27.472204 16.891921 32.320560 -6.091053 -26.953745 12 13 14 15 16 17 18 ... 41.798651 40.734935 40.285066 24.876177 8.442082 46.373463 72.652242 118120121122123124125 65.983901 81.140660 101.389698 92.784665 86.803528 66.813059 76.464152 126127128129130131132 85.562396 80.164720 55.046451 22.602751 38.602215 35.466808 28.565003 133134135136137138139 30.487396 27.515347 17.475536 49.119123 11.994736 14.701687 49.795201 140141142143144145146 5.664599 24.711067 20.426534 53.013693 5.758723 19.324367 41.190110 147148149151152153 14.189862 -19.275130 35.155615 20.525269 40.584670 18.702940 ... Aha! 100 times machine precision in not all that much when the numbers themselves are in double digits. In fact, one is over 100. The case that triggers the failure is #149 147 148 149 151 152 -1.598721e-14 -1.065814e-14 -2.842171e-14 -1.065814e-14 -2.131628e-14 which is 2 ULP off by my reckoning (scaling 35.15 to be between 0.5 and 1 makes the error 2.842e-14/64 = 4.44e-16 and [EMAIL PROTECTED] is 2.22e-16). So again, we might be too strict. I just wonder why we haven't heard of this on any other platforms. -- O__ Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
Peter Dalgaard [EMAIL PROTECTED] writes: Aha! 100 times machine precision in not all that much when the numbers themselves are in double digits. In fact, one is over 100. The case that triggers the failure is #149 147 148 149 151 152 -1.598721e-14 -1.065814e-14 -2.842171e-14 -1.065814e-14 -2.131628e-14 which is 2 ULP off by my reckoning (scaling 35.15 to be between 0.5 and 1 makes the error 2.842e-14/64 = 4.44e-16 and [EMAIL PROTECTED] is 2.22e-16). So again, we might be too strict. I just wonder why we haven't heard of this on any other platforms. I've fixed the precision requirement (for this and the reg-tests-1 issue) in the repository and what should become tomorrow's beta version. -- O__ Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
Peter Dalgaard wrote: M. Edward (Ed) Borasky [EMAIL PROTECTED] writes: [EMAIL PROTECTED] wrote: This looks more serious. 100 times machine precision is quite a large margin in these matters. Could you perhaps stick in a printout of the two terms and their difference? I have an ATLAS build on AMD64 and it passes all the checks, but it is using ATLAS 3.7.8, so you might want to try an upgrade. Attached ... you actually weren't very far off: ... print (f2[common]) 1 2 3 4 7 8 9 32.971099 37.113091 27.472204 16.891921 32.320560 -6.091053 -26.953745 12 13 14 15 16 17 18 ... 41.798651 40.734935 40.285066 24.876177 8.442082 46.373463 72.652242 118120121122123124125 65.983901 81.140660 101.389698 92.784665 86.803528 66.813059 76.464152 126127128129130131132 85.562396 80.164720 55.046451 22.602751 38.602215 35.466808 28.565003 133134135136137138139 30.487396 27.515347 17.475536 49.119123 11.994736 14.701687 49.795201 140141142143144145146 5.664599 24.711067 20.426534 53.013693 5.758723 19.324367 41.190110 147148149151152153 14.189862 -19.275130 35.155615 20.525269 40.584670 18.702940 ... Aha! 100 times machine precision in not all that much when the numbers themselves are in double digits. In fact, one is over 100. The case that triggers the failure is #149 147 148 149 151 152 -1.598721e-14 -1.065814e-14 -2.842171e-14 -1.065814e-14 -2.131628e-14 which is 2 ULP off by my reckoning (scaling 35.15 to be between 0.5 and 1 makes the error 2.842e-14/64 = 4.44e-16 and [EMAIL PROTECTED] is 2.22e-16). So again, we might be too strict. I just wonder why we haven't heard of this on any other platforms. I think it's an Atlas issue, and possibly an Atlas/Athlon32 issue. The built-in BLAS in R-beta don't show this. Is there enough detail on what's happening available for me to take this to the Atlas folks? They've done a lot of work, including assembler code, on Athlons and their 64-bit descendents. My main system, where I've been doing this testing, is a rather old Athlon T-Bird. Incidentally, even though Atlas does have most parameters set to pre-defined values for the Athlon/Linux, it does in fact make *some* decisions when it compiles, which may be why I'm showing this and nobody else is. I'm using Gentoo Linux, which recompiles nearly everything from source, including Atlas and R, when it does an install. Most of the other Linux distros have pre-compiled binaries for the various packages. Debian, for example, has pre-compiled Atlas libraries for P3, P4 and Athlon. __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
On Sun, 10 Apr 2005, M. Edward (Ed) Borasky wrote: Peter Dalgaard wrote: M. Edward (Ed) Borasky [EMAIL PROTECTED] writes: [EMAIL PROTECTED] wrote: This looks more serious. 100 times machine precision is quite a large margin in these matters. Could you perhaps stick in a printout of the two terms and their difference? I have an ATLAS build on AMD64 and it passes all the checks, but it is using ATLAS 3.7.8, so you might want to try an upgrade. Attached ... you actually weren't very far off: ... print (f2[common]) 1 2 3 4 7 8 9 32.971099 37.113091 27.472204 16.891921 32.320560 -6.091053 -26.95374512 13 14 15 16 17 18 ... 41.798651 40.734935 40.285066 24.876177 8.442082 46.373463 72.652242 118120121122123124 125 65.983901 81.140660 101.389698 92.784665 86.803528 66.813059 76.464152 126127128129130131 132 85.562396 80.164720 55.046451 22.602751 38.602215 35.466808 28.565003 133134135136137138 139 30.487396 27.515347 17.475536 49.119123 11.994736 14.701687 49.795201 140141142143144145 146 5.664599 24.711067 20.426534 53.013693 5.758723 19.324367 41.190110 147148149151152153 14.189862 -19.275130 35.155615 20.525269 40.584670 18.702940 ... Aha! 100 times machine precision in not all that much when the numbers themselves are in double digits. In fact, one is over 100. The case that triggers the failure is #149 147 148 149 151 152 -1.598721e-14 -1.065814e-14 -2.842171e-14 -1.065814e-14 -2.131628e-14 which is 2 ULP off by my reckoning (scaling 35.15 to be between 0.5 and 1 makes the error 2.842e-14/64 = 4.44e-16 and [EMAIL PROTECTED] is 2.22e-16). So again, we might be too strict. I just wonder why we haven't heard of this on any other platforms. I think it's an Atlas issue, and possibly an Atlas/Athlon32 issue. The built-in BLAS in R-beta don't show this. Is there enough detail on what's happening available for me to take this to the Atlas folks? They've done a lot of work, including assembler code, on Athlons and their 64-bit descendents. My main system, where I've been doing this testing, is a rather old Athlon T-Bird. Incidentally, even though Atlas does have most parameters set to pre-defined values for the Athlon/Linux, it does in fact make *some* decisions when it compiles, which may be why I'm showing this and nobody else is. I'm using Gentoo Linux, which recompiles nearly everything from source, including Atlas and R, when it does an install. Most of the other Linux distros have pre-compiled binaries for the various packages. Debian, for example, has pre-compiled Atlas libraries for P3, P4 and Athlon. I think the issue is ATLAS on your old Athlon. ATLAS 3.6.0 compiled from the sources works correctly with gcc-3.4.3 on my Athlon MP (and also on an Athlon XP), but AFAIR those have instructions the Athlon Thunderbird does not have. (Both my machines with such Athlons fried their motherboards, so I no longer have access to one.) Incidentally to Peter: ATLAS 3.7.8 is an unreleased unstable version, so I would hesitate to recommend it over 3.6.0. -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UKFax: +44 1865 272595 __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
Prof Brian Ripley [EMAIL PROTECTED] writes: I think the issue is ATLAS on your old Athlon. ATLAS 3.6.0 compiled from the sources works correctly with gcc-3.4.3 on my Athlon MP (and also on an Athlon XP), but AFAIR those have instructions the Athlon Thunderbird does not have. (Both my machines with such Athlons fried their motherboards, so I no longer have access to one.) Incidentally to Peter: ATLAS 3.7.8 is an unreleased unstable version, so I would hesitate to recommend it over 3.6.0. To be precise, it's a release on an unstable branch. Hasn't changed since 2004-07-23 though.. But you're right in principle; I had forgotten about that. -- O__ Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
[Rd] make check-all fails (PR#7784)
Full_Name: Ed Borasky Version: R-beta 2.1.0 2005-04-08 OS: Linux 2.6.11 GCC 3.3.5 Submission from: (NULL) (24.21.57.139) I downloaded the latest R-beta tarball and did a build with the default options. OS is Linux 2.6.11 and compiler is GCC 3.3.5. make check-all failed with the following message: make[3]: Entering directory `/home/znmeb/R-beta/tests' running code in 'reg-tests-1.R' ...make[3]: *** [reg-tests-1.Rout] Error 1 make[3]: Leaving directory `/home/znmeb/R-beta/tests' make[2]: *** [test-Reg] Error 2 make[2]: Leaving directory `/home/znmeb/R-beta/tests' make[1]: *** [test-all-basics] Error 1 make[1]: Leaving directory `/home/znmeb/R-beta/tests' make: *** [check-all] Error 2 I looked at tests/reg-tests-1.Rout.fail; it's 1427 lines long. The error given is ## Comments: ## PR 796 (aic in binomial models is often wrong) ## a1 - glm(cbind(ncases, ncontrols) ~ agegp + tobgp * alcgp, + data = esoph, family = binomial())$aic a1 [1] 236.9645 a2 - glm(ncases/(ncases+ncontrols) ~ agegp + tobgp * alcgp, + data = esoph, family = binomial(), weights=ncases+ncontrols)$aic a2 [1] 236.9645 stopifnot(a1 == a2) Error: a1 == a2 is not TRUE Execution halted I am running on an Athlon Thunderbird with Atlas 3.6.0 installed. If necessary, I can back Atlas out and run this again. __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
[EMAIL PROTECTED] writes: Full_Name: Ed Borasky Version: R-beta 2.1.0 2005-04-08 OS: Linux 2.6.11 GCC 3.3.5 Submission from: (NULL) (24.21.57.139) I downloaded the latest R-beta tarball and did a build with the default options. OS is Linux 2.6.11 and compiler is GCC 3.3.5. make check-all failed with the following message: make[3]: Entering directory `/home/znmeb/R-beta/tests' running code in 'reg-tests-1.R' ...make[3]: *** [reg-tests-1.Rout] Error 1 make[3]: Leaving directory `/home/znmeb/R-beta/tests' make[2]: *** [test-Reg] Error 2 make[2]: Leaving directory `/home/znmeb/R-beta/tests' make[1]: *** [test-all-basics] Error 1 make[1]: Leaving directory `/home/znmeb/R-beta/tests' make: *** [check-all] Error 2 I looked at tests/reg-tests-1.Rout.fail; it's 1427 lines long. The error given is ## Comments: ## PR 796 (aic in binomial models is often wrong) ## a1 - glm(cbind(ncases, ncontrols) ~ agegp + tobgp * alcgp, + data = esoph, family = binomial())$aic a1 [1] 236.9645 a2 - glm(ncases/(ncases+ncontrols) ~ agegp + tobgp * alcgp, + data = esoph, family = binomial(), weights=ncases+ncontrols)$aic a2 [1] 236.9645 stopifnot(a1 == a2) Error: a1 == a2 is not TRUE Execution halted I am running on an Athlon Thunderbird with Atlas 3.6.0 installed. If necessary, I can back Atlas out and run this again. Hmm, could you replace the a1 == a2 with all.equal(a1, a2) instead? (inside reg-tests-1.R of course) Asking for identity up to machine precision does look a bit optimistic... -- O__ Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
Peter Dalgaard wrote: [EMAIL PROTECTED] writes: Full_Name: Ed Borasky Version: R-beta 2.1.0 2005-04-08 OS: Linux 2.6.11 GCC 3.3.5 Submission from: (NULL) (24.21.57.139) I downloaded the latest R-beta tarball and did a build with the default options. OS is Linux 2.6.11 and compiler is GCC 3.3.5. make check-all failed with the following message: make[3]: Entering directory `/home/znmeb/R-beta/tests' running code in 'reg-tests-1.R' ...make[3]: *** [reg-tests-1.Rout] Error 1 make[3]: Leaving directory `/home/znmeb/R-beta/tests' make[2]: *** [test-Reg] Error 2 make[2]: Leaving directory `/home/znmeb/R-beta/tests' make[1]: *** [test-all-basics] Error 1 make[1]: Leaving directory `/home/znmeb/R-beta/tests' make: *** [check-all] Error 2 I looked at tests/reg-tests-1.Rout.fail; it's 1427 lines long. The error given is ## Comments: ## PR 796 (aic in binomial models is often wrong) ## a1 - glm(cbind(ncases, ncontrols) ~ agegp + tobgp * alcgp, + data = esoph, family = binomial())$aic a1 [1] 236.9645 a2 - glm(ncases/(ncases+ncontrols) ~ agegp + tobgp * alcgp, + data = esoph, family = binomial(), weights=ncases+ncontrols)$aic a2 [1] 236.9645 stopifnot(a1 == a2) Error: a1 == a2 is not TRUE Execution halted I am running on an Athlon Thunderbird with Atlas 3.6.0 installed. If necessary, I can back Atlas out and run this again. Hmm, could you replace the a1 == a2 with all.equal(a1, a2) instead? (inside reg-tests-1.R of course) Asking for identity up to machine precision does look a bit optimistic... That worked ... it got through reg-tests-1.R fine. However, it failed a little further down in the NA handling tests: running tests of NA handling functions make[3]: Entering directory `/home/znmeb/R-beta/tests' running code in 'nafns.R' ...make[3]: *** [nafns.Rout] Error 1 make[3]: Leaving directory `/home/znmeb/R-beta/tests' make[2]: *** [test-Nafns] Error 2 make[2]: Leaving directory `/home/znmeb/R-beta/tests' make[1]: *** [test-all-devel] Error 1 make[1]: Leaving directory `/home/znmeb/R-beta/tests' make: *** [check-all] Error 2 sm(fitted(gfit2)) length 153 with 42 NAs sm(resid(gfit2)) length 153 with 42 NAs sm(predict(gfit2)) length 153 with 42 NAs (pp2 - predict(gfit2, nd)) 6 25 26 27 NA -16.177404 1.688479 NA stopifnot(all.equal(pp, pp2)) ## more precise tests. f1 - fitted(gfit) f2 - fitted(gfit2) common - match(names(f1), names(f2)) stopifnot(max(abs(f1 - f2[common])) 100*.Machine$double.eps) Error: max(abs(f1 - f2[common])) 100 * .Machine$double.eps is not TRUE Execution halted tests/nafns.Rout.fail __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
M. Edward (Ed) Borasky [EMAIL PROTECTED] writes: [snip] Hmm, could you replace the a1 == a2 with all.equal(a1, a2) instead? (inside reg-tests-1.R of course) Asking for identity up to machine precision does look a bit optimistic... That worked ... it got through reg-tests-1.R fine. However, it failed a little further down in the NA handling tests: running tests of NA handling functions make[3]: Entering directory `/home/znmeb/R-beta/tests' running code in 'nafns.R' ...make[3]: *** [nafns.Rout] Error 1 make[3]: Leaving directory `/home/znmeb/R-beta/tests' make[2]: *** [test-Nafns] Error 2 make[2]: Leaving directory `/home/znmeb/R-beta/tests' make[1]: *** [test-all-devel] Error 1 make[1]: Leaving directory `/home/znmeb/R-beta/tests' make: *** [check-all] Error 2 sm(fitted(gfit2)) length 153 with 42 NAs sm(resid(gfit2)) length 153 with 42 NAs sm(predict(gfit2)) length 153 with 42 NAs (pp2 - predict(gfit2, nd)) 6 25 26 27 NA -16.177404 1.688479 NA stopifnot(all.equal(pp, pp2)) ## more precise tests. f1 - fitted(gfit) f2 - fitted(gfit2) common - match(names(f1), names(f2)) stopifnot(max(abs(f1 - f2[common])) 100*.Machine$double.eps) Error: max(abs(f1 - f2[common])) 100 * .Machine$double.eps is not TRUE Execution halted tests/nafns.Rout.fail This looks more serious. 100 times machine precision is quite a large margin in these matters. Could you perhaps stick in a printout of the two terms and their difference? I have an ATLAS build on AMD64 and it passes all the checks, but it is using ATLAS 3.7.8, so you might want to try an upgrade. -- O__ Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 __ R-devel@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] make check-all fails (PR#7784)
[EMAIL PROTECTED] wrote: This looks more serious. 100 times machine precision is quite a large margin in these matters. Could you perhaps stick in a printout of the two terms and their difference? I have an ATLAS build on AMD64 and it passes all the checks, but it is using ATLAS 3.7.8, so you might want to try an upgrade. Attached ... you actually weren't very far off: print (max(abs(f1 - f2[common]))) [1] 2.842171e-14 print (100*.Machine$double.eps) [1] 2.220446e-14 stopifnot(max(abs(f1 - f2[common])) 100*.Machine$double.eps) Error: max(abs(f1 - f2[common])) 100 * .Machine$double.eps is not TRUE Execution halted I'll go ahead and try ATLAS 3.7.8, but that takes a couple of hours to build. I've also got a Pentium III I can test this on. R : Copyright 2005, The R Foundation for Statistical Computing Version 2.1.0 beta (2005-04-08), ISBN 3-900051-07-0 R is free software and comes with ABSOLUTELY NO WARRANTY. You are welcome to redistribute it under certain conditions. Type 'license()' or 'licence()' for distribution details. R is a collaborative project with many contributors. Type 'contributors()' for more information and 'citation()' on how to cite R or R packages in publications. Type 'demo()' for some demos, 'help()' for on-line help, or 'help.start()' for a HTML browser interface to help. Type 'q()' to quit R. ## Tests of functions handling NAs in fits ## These functions were introduced in 1.3.0. ## They are used by lm and glm in base R, and by ## packages MASS, rpart and survival. dim(airquality) [1] 153 6 nd - airquality[c(6,25:27), ] sm - function(x) cat(length, length(x), with, sum(is.na(x)), NAs\n) # default is to omit some rows fit - lm(Ozone ~ ., data=airquality, na.action=na.omit) summary(fit) Call: lm(formula = Ozone ~ ., data = airquality, na.action = na.omit) Residuals: Min 1Q Median 3Q Max -37.014 -12.284 -3.302 8.454 95.348 Coefficients: Estimate Std. Error t value Pr(|t|) (Intercept) -64.11632 23.48249 -2.730 0.00742 ** Solar.R 0.050270.02342 2.147 0.03411 * Wind -3.318440.64451 -5.149 1.23e-06 *** Temp 1.895790.27389 6.922 3.66e-10 *** Month-3.039961.51346 -2.009 0.04714 * Day 0.273880.22967 1.192 0.23576 --- Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 Residual standard error: 20.86 on 105 degrees of freedom Multiple R-Squared: 0.6249, Adjusted R-squared: 0.6071 F-statistic: 34.99 on 5 and 105 DF, p-value: 2.2e-16 sm(fitted(fit)) length 111 with 0 NAs sm(resid(fit)) length 111 with 0 NAs sm(predict(fit)) length 111 with 0 NAs (pp - predict(fit, nd)) 6 25 26 27 NA -16.177404 1.688479 NA fit2 - lm(Ozone ~ ., data=airquality, na.action=na.exclude) summary(fit2) # same as before Call: lm(formula = Ozone ~ ., data = airquality, na.action = na.exclude) Residuals: Min 1Q Median 3Q Max -37.014 -12.284 -3.302 8.454 95.348 Coefficients: Estimate Std. Error t value Pr(|t|) (Intercept) -64.11632 23.48249 -2.730 0.00742 ** Solar.R 0.050270.02342 2.147 0.03411 * Wind -3.318440.64451 -5.149 1.23e-06 *** Temp 1.895790.27389 6.922 3.66e-10 *** Month-3.039961.51346 -2.009 0.04714 * Day 0.273880.22967 1.192 0.23576 --- Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 Residual standard error: 20.86 on 105 degrees of freedom Multiple R-Squared: 0.6249, Adjusted R-squared: 0.6071 F-statistic: 34.99 on 5 and 105 DF, p-value: 2.2e-16 sm(fitted(fit2)) length 153 with 42 NAs sm(resid(fit2)) length 153 with 42 NAs sm(predict(fit2)) length 153 with 42 NAs (pp2 - predict(fit2, nd)) 6 25 26 27 NA -16.177404 1.688479 NA ## same as before: napredict is only applied to predictions on the ## original data, following Therneau's original code (and S-PLUS). ## However, as from R 1.8.0 there is a separate na.action arg to predict.lm() stopifnot(all.equal(pp, pp2)) ## should fail try(fit3 - lm(Ozone ~ ., data=airquality, na.action=na.fail)) Error in na.fail.default(list(Ozone = c(41, 36, 12, 18, NA, 28, 23, 19, : missing values in object ## more precise tests. f1 - fitted(fit) f2 - fitted(fit2) common - match(names(f1), names(f2)) stopifnot(max(abs(f1 - f2[common])) 100*.Machine$double.eps) stopifnot(all(is.na(f2[-common]))) r1 - resid(fit) r2 - resid(fit2) common - match(names(r1), names(r2)) stopifnot(max(abs(r1 - r2[common])) 100*.Machine$double.eps) stopifnot(all(is.na(r2[-common]))) p1 - predict(fit) p2 - predict(fit2) common - match(names(p1), names(p2)) stopifnot(max(abs(p1 - p2[common])) 100*.Machine$double.eps) stopifnot(all(is.na(p2[-common]))) ### now try out glm gfit - glm(Ozone ~ ., data=airquality,
