expr command on arthmetic
expressions. The detailed parsing rules for arithmetic expressions
depend on the particular Unix implementation, but they are more or
less like in C.
Here are some examples:
# integer division truncates
% expr 7 / 2
3
# the percent sign is used to compute integer remainder
% expr 7%2
# floating point propagates
% expr 7.0 / 2
3.5
% expr sin(.5)+cos(.9)
1.10103550687
% # a zero in front of number means to interpret as octal
% expr 017 + 01
16
% # a 0x in front means to interpret as hex
% expr 0xA + 1
11
% # numbers can be treated like strings!
% string length 100.34
6
% string range 100.34 0 2
100
More: See http://www.tcl.tk/man/tcl8.4/TclCmd/expr.htm.
expr.)
- abs(x)
- asin(x)
- acos(x)
- atan(x)
- atan2(y,x)
atan2 returns the angle theta of the polar
coordinates returned when (x,y) is converted to (r, theta).
- ceil(x)
- cos(x)
- cosh(x)
- double(x)
returns x as a double or floating point.
- exp(x)
returns e^x
- floor(x)
- fmod(x,y)
returns the floating point remainder of x/y.
- hypot(x,y)
returns the square root of the sum of x squared plus
y squared, the length of the line from (0,0) to (x,y).
- int(x)
truncates x to an integer.
- log(x)
returns the natural log of x.
- log10(x)
returns log base 10 of x.
- pow(x,y)
returns x to the y power.
- round(x)
- sin(x)
- sinh(x)
- sqrt(x)
- tan(x)
- tanh(x)