Perform a Z-test of the null hypothesis
mean (x) ==m for a sample x from a normal distribution with unknown mean and known variance v. Under the null, the test statistic z follows a standard normal distribution.With the optional argument string alt, the alternative of interest can be selected. If alt is
"!="or"<>", the null is tested against the two-sided alternativemean (x) !=m. If alt is">", the one-sided alternativemean (x) >m is considered. Similarly for"<", the one-sided alternativemean (x) <m is considered. The default is the two-sided case.The p-value of the test is returned in pval.
If no output argument is given, the p-value of the test is displayed along with some information.