APREPRO Predefined Variables

A few commonly used variables are predefined in APREPRO. These are listed below. The default output format is specified as a C language format string, see your C language documentation for more information. The default format and comment variables are defined with a leading underscore in their name so they can be redefined without generating an error message.

Predefined Variables

Name

Value

Description

PI

3.14159265358979323846

p

PI_2

1.57079632679489661923

p/2

SQRT2

1.41421356237309504880

DEG

57.2957795130823208768

180 /p degrees per radian

RAD

0.01745329251994329576

p/180 radians per degree

E

2.71828182845904523536

base of natural logarithm

GAMMA

0.57721566490153286060

euler-mascheroni constant1

PHI

1.61803398874989484820

golden ratio (+ 1)/2

VERSION

Varies, string value

current version of CUBIT

_ FORMAT

"%.10g"

default output format

_C_

"#"

default comment character

   

1The euler-mascheroni constant is defined as the limit of 1 + 1/2 + ... + 1/s - log(s) as s approaches infinity.

Note that the output format is used to output both integers and floating point numbers. Therefore, it should use the %g format descriptor which will use either the decimal (%d), exponential (%e), or float (%f) format, whichever is shorter, with insignificant zeros suppressed. The table below illustrates the effect of different format specifications on the output of the variable PI and the value 1.0 . See the documentation of your C compiler for more information. For most cases, the default value is sufficient.

Effect of Various Output Format Specifications

Format

PI Output

1.0 Output

%.10g

3.141592654

1

%.10e

3.1415926536e+00

1.0000000000e+00

%.10f

3.1415926536

1.0000000000

%.10d

1413754136

0000000000

The comment character should be set to the character that the program which will read the processed file uses as a comment character. The default value of "$" is the comment character used by the SEACAS codes at Sandia National Laboratories. The -c command line option * automatically changes the value of the comment variable to match the character specified on the command line.