It's likely you caught one of the interim xts R-Forge releases with a (known) bug in subsetting.
The sessionInfo() call would show you the version in question, but the answer/fix is to update to either the latest on R-forge, or the new version 0.8-0 making its way to CRAN mirrors now. Best, Jeff On Feb 22, 2011, at 9:01 PM, Worik Stanton <[email protected]> wrote: > I cannot get a small example to illustrate this, as the problem > disappears in strange ways. So this email will have a lot of text. > > I do not know how to get xts version but here is the R version > >> R.version > _ > platform i686-pc-linux-gnu > arch i686 > os linux-gnu > system i686, linux-gnu > status > major 2 > minor 11.1 > year 2010 > month 05 > day 31 > svn rev 52157 > language R > version.string R version 2.11.1 (2010-05-31) > > > I have a xts caled A.x > >> class(A.x) > [1] "xts" "zoo" >> names(A.x) > [1] "Lev" "200MA" "RF" "Ret" >>> c(start(A.x), end(A.x)) > [1] "1928-01-31" "2010-07-31" >> > > (It is a processed version of S&P500 monthly index) > > When I subset A.x by date the 4th column (Ret) gets mangled. > > Below are screeds of data, sorry, but if I shrink these the problem > disappears. > > cheers > Worik > >> Z <- merge(A.x["1929::2010",4], A.x[,4]) >> Y <- merge(Z, Z[,1]-Z[,2]) >> Y > 1928-01-31 NA NA NA > 1928-02-29 NA -1.764371e-02 NA > 1928-03-31 NA 1.083430e-01 NA > 1928-04-30 NA 3.240983e-02 NA > 1928-05-31 NA 1.265823e-02 NA > 1928-06-30 NA -4.050000e-02 NA > 1928-07-31 NA 1.250651e-02 NA > 1928-08-31 NA 7.411220e-02 NA > 1928-09-30 NA 2.395783e-02 NA > 1928-10-31 NA 1.450632e-02 NA > 1928-11-30 NA 1.199262e-01 NA > 1928-12-31 NA 2.883031e-03 NA > 1929-01-31 1.720000e+00 5.708419e-02 1.662916e+00 > 1929-02-28 1.130000e+00 -5.827506e-03 1.135828e+00 > 1929-03-31 6.700000e-01 -2.344666e-03 6.723447e-01 > 1929-04-30 1.900000e-01 1.605954e-02 1.739405e-01 > 1929-05-31 3.000000e-02 -4.279106e-02 7.279106e-02 > 1929-06-30 1.300000e-01 1.123641e-01 1.763592e-02 > 1929-07-31 3.000000e-01 4.561912e-02 2.543809e-01 > 1929-08-31 2.100000e-01 9.799169e-02 1.120083e-01 > 1929-09-30 1.600000e-01 -4.888048e-02 2.088805e-01 > 1929-10-31 1.800000e-01 -1.992706e-01 3.792706e-01 > 1929-11-30 1.800000e-01 -1.337474e-01 3.137474e-01 > 1929-12-31 1.800000e-01 2.533461e-02 1.546654e-01 > 1930-01-31 1.700000e-01 6.247086e-02 1.075291e-01 > 1930-02-28 1.200000e-01 2.150066e-02 9.849934e-02 > 1930-03-31 7.000000e-02 7.989691e-02 -9.896907e-03 > 1930-04-30 5.000000e-02 -9.546539e-03 5.954654e-02 > 1930-05-31 5.000000e-02 -1.646586e-02 6.646586e-02 > 1930-06-30 6.000000e-02 -1.645570e-01 2.245570e-01 > 1930-07-31 1.100000e-01 3.665689e-02 7.334311e-02 > 1930-08-31 1.500000e-01 7.543612e-03 1.424564e-01 > 1930-09-30 1.600000e-01 -1.300889e-01 2.900889e-01 > 1930-10-31 1.600000e-01 -8.875740e-02 2.487574e-01 > 1930-11-30 1.200000e-01 -2.184179e-02 1.418418e-01 > 1930-12-31 1.600000e-01 -7.423054e-02 2.342305e-01 > 1931-01-31 NA 4.889179e-02 NA > 1931-02-28 -1.764371e-02 1.143567e-01 -1.320005e-01 > 1931-03-31 1.083430e-01 -6.915784e-02 1.775008e-01 > 1931-04-30 3.240983e-02 -9.586579e-02 1.282756e-01 > 1931-05-31 1.265823e-02 -1.371769e-01 1.498352e-01 > 1931-06-30 -4.050000e-02 1.390169e-01 -1.795169e-01 > 1931-07-31 1.250651e-02 -7.417397e-02 8.668049e-02 > 1931-08-31 7.411220e-02 9.468318e-03 6.464388e-02 > 1931-09-30 2.395783e-02 -2.994228e-01 3.233806e-01 > 1931-10-31 1.450632e-02 8.444902e-02 -6.994270e-02 > 1931-11-30 1.199262e-01 -9.781576e-02 2.177420e-01 > 1931-12-31 2.883031e-03 -1.452632e-01 1.481462e-01 > 1932-01-31 5.708419e-02 -2.832512e-02 8.540931e-02 > 1932-02-29 -5.827506e-03 5.069708e-02 -5.652459e-02 > 1932-03-31 -2.344666e-03 -1.182147e-01 1.158701e-01 > 1932-04-30 1.605954e-02 -2.024624e-01 2.185219e-01 > 1932-05-31 -4.279106e-02 -2.332762e-01 1.904851e-01 > 1932-06-30 1.123641e-01 -8.948546e-03 1.213126e-01 > 1932-07-31 4.561912e-02 3.769752e-01 -3.313561e-01 > 1932-08-31 9.799169e-02 3.754098e-01 -2.774181e-01 > 1932-09-30 -4.888048e-02 -3.694875e-02 -1.193173e-02 > 1932-10-31 -1.992706e-01 -1.386139e-01 -6.065670e-02 > 1932-11-30 -1.337474e-01 -5.890805e-02 -7.483937e-02 > 1932-12-31 2.533461e-02 5.190840e-02 -2.657379e-02 > 1933-01-31 6.247086e-02 7.256894e-03 5.521397e-02 > 1933-02-28 2.150066e-02 -1.844380e-01 2.059387e-01 > 1933-03-31 7.989691e-02 3.356890e-02 4.632800e-02 > 1933-04-30 -9.546539e-03 4.222222e-01 -4.317688e-01 > : > : > : > 2001-09-30 6.406681e-02 -8.074556e-02 1.448124e-01 > 2001-10-31 8.126906e-02 1.907934e-02 6.218972e-02 > 2001-11-30 6.058320e-02 7.668909e-02 -1.610589e-02 > 2001-12-31 5.758811e-02 8.766631e-03 4.882148e-02 > 2002-01-31 4.180194e-02 -1.458492e-02 5.638686e-02 > 2002-02-28 -3.106290e-02 -1.928891e-02 -1.177399e-02 > 2002-03-31 3.999836e-02 3.761344e-02 2.384916e-03 > 2002-04-30 3.872519e-02 -6.060114e-02 9.932633e-02 > 2002-05-31 -2.358079e-02 -7.341115e-03 -1.623967e-02 > 2002-06-30 5.545330e-02 -7.120423e-02 1.266575e-01 > 2002-07-31 -3.119457e-02 -7.792881e-02 4.673424e-02 > 2002-08-31 -4.948639e-03 6.546929e-03 -1.149557e-02 > 2002-09-30 -2.738231e-02 -1.085825e-01 8.120014e-02 > 2002-10-31 6.325486e-02 8.793250e-02 -2.467764e-02 > 2002-11-30 2.032765e-02 5.880188e-02 -3.847423e-02 > 2002-12-31 5.885990e-02 -5.871740e-02 1.175773e-01 > 2003-01-31 -5.023653e-02 -2.614587e-02 -2.409065e-02 > 2003-02-28 -1.891104e-02 -1.502581e-02 -3.885236e-03 > 2003-03-31 9.776745e-02 9.682245e-03 8.808521e-02 > 2003-04-30 -3.007423e-02 8.233138e-02 -1.124056e-01 > 2003-05-31 -2.052851e-02 5.263665e-02 -7.316516e-02 > 2003-06-30 2.465663e-02 1.277463e-02 1.188200e-02 > 2003-07-31 -1.562116e-02 1.763946e-02 -3.326062e-02 > 2003-08-31 6.207876e-02 1.946365e-02 4.261511e-02 > 2003-09-30 -5.278210e-02 -1.058773e-02 -4.219437e-02 > 2003-10-31 -4.240781e-03 5.654044e-02 -6.078122e-02 > 2003-11-30 -7.878209e-02 8.787858e-03 -8.756995e-02 > 2003-12-31 4.905010e-03 5.240762e-02 -4.750261e-02 > 2004-01-31 3.545729e-02 1.835153e-02 1.710576e-02 > 2004-02-29 -9.112422e-02 1.389535e-02 -1.050196e-01 > 2004-03-31 -6.331616e-02 -1.508434e-02 -4.823182e-02 > 2004-04-30 7.764807e-02 -1.567786e-02 9.332593e-02 > 2004-05-31 6.710015e-03 1.369499e-02 -6.984975e-03 > 2004-06-30 -2.433036e-02 1.943932e-02 -4.376967e-02 > 2004-07-31 -9.849356e-03 -3.314085e-02 2.329149e-02 > 2004-08-31 -6.253705e-02 4.016675e-03 -6.655372e-02 > 2004-09-30 -8.074556e-02 1.082333e-02 -9.156889e-02 > 2004-10-31 1.907934e-02 1.527709e-02 3.802254e-03 > 2004-11-30 7.668909e-02 4.044818e-02 3.624091e-02 > 2004-12-31 8.766631e-03 3.401843e-02 -2.525180e-02 > 2005-01-31 -1.458492e-02 -2.437486e-02 9.789944e-03 > 2005-02-28 -1.928891e-02 2.103283e-02 -4.032173e-02 > 2005-03-31 3.761344e-02 -1.768947e-02 5.530291e-02 > 2005-04-30 -6.060114e-02 -1.895654e-02 -4.164460e-02 > 2005-05-31 -7.341115e-03 3.179020e-02 -3.913132e-02 > 2005-06-30 -7.120423e-02 1.433108e-03 -7.263733e-02 > 2005-07-31 -7.792881e-02 3.717322e-02 -1.151020e-01 > 2005-08-31 6.546929e-03 -9.129511e-03 1.567644e-02 > 2005-09-30 -1.085825e-01 8.095481e-03 -1.166779e-01 > 2005-10-31 8.793250e-02 -1.667949e-02 1.046120e-01 > 2005-11-30 5.880188e-02 3.778370e-02 2.101818e-02 > 2005-12-31 -5.871740e-02 3.544358e-04 -5.907184e-02 > 2006-01-31 -2.614587e-02 2.647700e-02 -5.262287e-02 > 2006-02-28 -1.502581e-02 2.705295e-03 -1.773110e-02 > 2006-03-31 9.682245e-03 1.244575e-02 -2.763504e-03 > 2006-04-30 8.233138e-02 1.341893e-02 6.891245e-02 > 2006-05-31 5.263665e-02 -2.874538e-02 8.138203e-02 > 2006-06-30 1.277463e-02 1.327710e-03 1.144692e-02 > 2006-07-31 1.763946e-02 6.163661e-03 1.147580e-02 > 2006-08-31 1.946365e-02 2.375707e-02 -4.293421e-03 > 2006-09-30 -1.058773e-02 2.575373e-02 -3.634146e-02 > 2006-10-31 5.654044e-02 3.256648e-02 2.397396e-02 > 2006-11-30 8.787858e-03 1.898470e-02 -1.019684e-02 > 2006-12-31 5.240762e-02 1.402475e-02 3.838287e-02 > 2007-01-31 1.835153e-02 1.510802e-02 3.243511e-03 > 2007-02-28 1.389535e-02 -1.950030e-02 3.339565e-02 > 2007-03-31 -1.508434e-02 1.115994e-02 -2.624428e-02 > 2007-04-30 -1.567786e-02 4.428216e-02 -5.996002e-02 > 2007-05-31 1.369499e-02 3.485995e-02 -2.116496e-02 > 2007-06-30 1.943932e-02 -1.660254e-02 3.604186e-02 > 2007-07-31 -3.314085e-02 -3.096746e-02 -2.173394e-03 > 2007-08-31 4.016675e-03 1.496826e-02 -1.095158e-02 > 2007-09-30 1.082333e-02 3.735960e-02 -2.653627e-02 > 2007-10-31 1.527709e-02 1.590409e-02 -6.270021e-04 > 2007-11-30 4.044818e-02 -4.182397e-02 8.227215e-02 > 2007-12-31 3.401843e-02 -6.920090e-03 4.093852e-02 > 2008-01-31 -2.437486e-02 -5.997385e-02 3.559899e-02 > 2008-02-29 2.103283e-02 -3.245979e-02 5.349262e-02 > 2008-03-31 -1.768947e-02 -4.327525e-03 -1.336194e-02 > 2008-04-30 -1.895654e-02 4.869178e-02 -6.764832e-02 > 2008-05-31 3.179020e-02 1.295084e-02 1.883936e-02 > 2008-06-30 1.433108e-03 -8.422389e-02 8.565700e-02 > 2008-07-31 3.717322e-02 -8.409418e-03 4.558264e-02 > 2008-08-31 -9.129511e-03 1.447345e-02 -2.360296e-02 > 2008-09-30 8.095481e-03 -8.900728e-02 9.710276e-02 > 2008-10-31 -1.667949e-02 -1.679282e-01 1.512487e-01 > 2008-11-30 3.778370e-02 -7.177816e-02 1.095619e-01 > 2008-12-31 3.544358e-04 1.053659e-02 -1.018215e-02 > 2009-01-31 2.647700e-02 -8.418612e-02 1.106631e-01 > 2009-02-28 2.705295e-03 -1.061347e-01 1.088400e-01 > 2009-03-31 1.244575e-02 8.743881e-02 -7.499306e-02 > 2009-04-30 1.341893e-02 9.562540e-02 -8.220646e-02 > 2009-05-31 -2.874538e-02 5.586690e-02 -8.461228e-02 > 2009-06-30 1.327710e-03 1.997108e-03 -6.693984e-04 > 2009-07-31 6.163661e-03 7.553988e-02 -6.937622e-02 > 2009-08-31 2.375707e-02 3.605340e-02 -1.229633e-02 > 2009-09-30 2.575373e-02 3.728858e-02 -1.153485e-02 > 2009-10-31 3.256648e-02 -1.855341e-02 5.111988e-02 > 2009-11-30 1.898470e-02 5.996658e-02 -4.098189e-02 > 2009-12-31 1.402475e-02 1.930693e-02 -5.282174e-03 > 2010-01-31 1.510802e-02 -3.591852e-02 5.102654e-02 > 2010-02-28 -1.950030e-02 3.093380e-02 -5.043410e-02 > 2010-03-31 1.115994e-02 6.032170e-02 -4.916176e-02 > 2010-04-30 4.428216e-02 1.579164e-02 2.849052e-02 > 2010-05-31 3.485995e-02 -7.976831e-02 1.146283e-01 > 2010-06-30 -1.660254e-02 -5.227779e-02 3.567525e-02 > 2010-07-31 -3.096746e-02 7.003093e-02 -1.009984e-01 >> sum(na.omit(Y[,3])) > [1] 6.994696 >> > > > It is not a problem with merge as illustrated below... >> A.x[,4] > Ret > 1928-01-31 NA > 1928-02-29 -1.764371e-02 > 1928-03-31 1.083430e-01 > 1928-04-30 3.240983e-02 > 1928-05-31 1.265823e-02 > 1928-06-30 -4.050000e-02 > 1928-07-31 1.250651e-02 > 1928-08-31 7.411220e-02 > 1928-09-30 2.395783e-02 > 1928-10-31 1.450632e-02 > 1928-11-30 1.199262e-01 > 1928-12-31 2.883031e-03 > 1929-01-31 5.708419e-02 > 1929-02-28 -5.827506e-03 > 1929-03-31 -2.344666e-03 > 1929-04-30 1.605954e-02 > 1929-05-31 -4.279106e-02 > : > : > : > 1970-02-28 5.575161e-02 > 1970-03-31 4.357730e-03 > 1970-04-30 -8.747074e-02 > 1970-05-31 -5.777728e-02 > 1970-06-30 -4.663631e-02 > 1970-07-31 7.687028e-02 > 1970-08-31 4.778998e-02 > 1970-09-30 3.618744e-02 > 1970-10-31 -8.312546e-03 > 1970-11-30 5.057046e-02 > 1970-12-31 5.974776e-02 > 1971-01-31 4.319049e-02 > 1971-02-28 1.168123e-02 > 1971-03-31 3.937983e-02 > 1971-04-30 3.887935e-02 > 1971-05-31 -3.905711e-02 > 1971-06-30 3.312228e-03 > 1971-07-31 -3.871620e-02 > 1971-08-31 3.880526e-02 > 1971-09-30 -4.433059e-03 > 1971-10-31 -3.914985e-02 > 1971-11-30 2.120870e-04 > 1971-12-31 8.883940e-02 > 1972-01-31 2.057011e-02 > 1972-02-29 2.770806e-02 > 1972-03-31 8.257537e-03 > 1972-04-30 6.809705e-03 > : > : > : > 2009-03-31 8.743881e-02 > 2009-04-30 9.562540e-02 > 2009-05-31 5.586690e-02 > 2009-06-30 1.997108e-03 > 2009-07-31 7.553988e-02 > 2009-08-31 3.605340e-02 > 2009-09-30 3.728858e-02 > 2009-10-31 -1.855341e-02 > 2009-11-30 5.996658e-02 > 2009-12-31 1.930693e-02 > 2010-01-31 -3.591852e-02 > 2010-02-28 3.093380e-02 > 2010-03-31 6.032170e-02 > 2010-04-30 1.579164e-02 > 2010-05-31 -7.976831e-02 > 2010-06-30 -5.227779e-02 > 2010-07-31 7.003093e-02 > >> A.x["1929::2010",4] > Ret > 1929-01-31 1.720000e+00 > 1929-02-28 1.130000e+00 > 1929-03-31 6.700000e-01 > 1929-04-30 1.900000e-01 > 1929-05-31 3.000000e-02 > 1929-06-30 1.300000e-01 > 1929-07-31 3.000000e-01 > 1929-08-31 2.100000e-01 > 1929-09-30 1.600000e-01 > 1929-10-31 1.800000e-01 > 1929-11-30 1.800000e-01 > 1929-12-31 1.800000e-01 > 1930-01-31 1.700000e-01 > 1930-02-28 1.200000e-01 > 1930-03-31 7.000000e-02 > 1930-04-30 5.000000e-02 > 1930-05-31 5.000000e-02 > 1930-06-30 6.000000e-02 > 1930-07-31 1.100000e-01 > : > : > : > 2003-03-31 9.776745e-02 > 2003-04-30 -3.007423e-02 > 2003-05-31 -2.052851e-02 > 2003-06-30 2.465663e-02 > 2003-07-31 -1.562116e-02 > 2003-08-31 6.207876e-02 > 2003-09-30 -5.278210e-02 > 2003-10-31 -4.240781e-03 > 2003-11-30 -7.878209e-02 > 2003-12-31 4.905010e-03 > 2004-01-31 3.545729e-02 > 2004-02-29 -9.112422e-02 > 2004-03-31 -6.331616e-02 > 2004-04-30 7.764807e-02 > 2004-05-31 6.710015e-03 > 2004-06-30 -2.433036e-02 > 2004-07-31 -9.849356e-03 > 2004-08-31 -6.253705e-02 > 2004-09-30 -8.074556e-02 > 2004-10-31 1.907934e-02 > 2004-11-30 7.668909e-02 > 2004-12-31 8.766631e-03 > 2005-01-31 -1.458492e-02 > 2005-02-28 -1.928891e-02 > 2005-03-31 3.761344e-02 > 2005-04-30 -6.060114e-02 > 2005-05-31 -7.341115e-03 > 2005-06-30 -7.120423e-02 > 2005-07-31 -7.792881e-02 > 2005-08-31 6.546929e-03 > 2005-09-30 -1.085825e-01 > 2005-10-31 8.793250e-02 > 2005-11-30 5.880188e-02 > 2005-12-31 -5.871740e-02 > 2006-01-31 -2.614587e-02 > 2006-02-28 -1.502581e-02 > 2006-03-31 9.682245e-03 > 2006-04-30 8.233138e-02 > 2006-05-31 5.263665e-02 > 2006-06-30 1.277463e-02 > 2006-07-31 1.763946e-02 > 2006-08-31 1.946365e-02 > 2006-09-30 -1.058773e-02 > 2006-10-31 5.654044e-02 > 2006-11-30 8.787858e-03 > 2006-12-31 5.240762e-02 > 2007-01-31 1.835153e-02 > 2007-02-28 1.389535e-02 > 2007-03-31 -1.508434e-02 > 2007-04-30 -1.567786e-02 > 2007-05-31 1.369499e-02 > 2007-06-30 1.943932e-02 > 2007-07-31 -3.314085e-02 > 2007-08-31 4.016675e-03 > 2007-09-30 1.082333e-02 > 2007-10-31 1.527709e-02 > 2007-11-30 4.044818e-02 > 2007-12-31 3.401843e-02 > 2008-01-31 -2.437486e-02 > 2008-02-29 2.103283e-02 > 2008-03-31 -1.768947e-02 > 2008-04-30 -1.895654e-02 > 2008-05-31 3.179020e-02 > 2008-06-30 1.433108e-03 > 2008-07-31 3.717322e-02 > 2008-08-31 -9.129511e-03 > 2008-09-30 8.095481e-03 > 2008-10-31 -1.667949e-02 > 2008-11-30 3.778370e-02 > 2008-12-31 3.544358e-04 > 2009-01-31 2.647700e-02 > 2009-02-28 2.705295e-03 > 2009-03-31 1.244575e-02 > 2009-04-30 1.341893e-02 > 2009-05-31 -2.874538e-02 > 2009-06-30 1.327710e-03 > 2009-07-31 6.163661e-03 > 2009-08-31 2.375707e-02 > 2009-09-30 2.575373e-02 > 2009-10-31 3.256648e-02 > 2009-11-30 1.898470e-02 > 2009-12-31 1.402475e-02 > 2010-01-31 1.510802e-02 > 2010-02-28 -1.950030e-02 > 2010-03-31 1.115994e-02 > 2010-04-30 4.428216e-02 > 2010-05-31 3.485995e-02 > 2010-06-30 -1.660254e-02 > 2010-07-31 -3.096746e-02 > > -- > Dig it out of the ground > Melt it down > Bury it > Guard it > > _______________________________________________ > [email protected] mailing list > https://stat.ethz.ch/mailman/listinfo/r-sig-finance > -- Subscriber-posting only. If you want to post, subscribe first. > -- Also note that this is not the r-help list where general R questions > should go. _______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-sig-finance -- Subscriber-posting only. If you want to post, subscribe first. -- Also note that this is not the r-help list where general R questions should go.
