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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 | .TH "math" 1 "Wed Dec 16 2015" "Version 2.2.0" "fish" \" -*- nroff -*-
.ad l
.nh
.SH NAME
\fBmath\fP -- Perform mathematics calculations
.PP
.SS "Synopsis"
.PP
.nf
\fBmath\fP EXPRESSION
.fi
.PP
.SS "Description"
\fCmath\fP is used to perform mathematical calculations\&. It is a very thin wrapper for the bc program, which makes it possible to specify an expression from the command line without using non-standard extensions or a pipeline\&.
.PP
For a description of the syntax supported by math, see the manual for the bc program\&. Keep in mind that parameter expansion takes place on any expressions before they are evaluated\&. This can be very useful in order to perform calculations involving shell variables or the output of command substitutions, but it also means that parenthesis have to be escaped\&.
.SS "Examples"
\fCmath 1+1\fP outputs 2\&.
.PP
\fCmath $status-128\fP outputs the numerical exit status of the last command minus 128\&.
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