Table of Contents

• 1. cvr
  • 1.1. Syntax
  • 1.2. Stack Effects
  • 1.3. Description
  • 1.4. PostScript Level
  • 1.5. Examples
  • 1.6. Common Use Cases
    • 1.6.1. Ensuring Real Arithmetic
    • 1.6.2. Configuration Parsing
  • 1.7. Common Pitfalls
  • 1.8. Error Conditions
  • 1.9. See Also

1. cvr

Converts a number or string to a real number.

1.1. Syntax

num cvr → real
string cvr → real

1.2. Stack Effects

Table 1. Before

Level	Object
0	num (integer or real) or string

Table 2. After

Level	Object
0	real (real number result)

1.3. Description

cvr (convert to real) converts an integer, real, or string to a real number:

• Integer operand: Converts to real

• Real operand: Returns it unchanged

• String operand: Parses as PostScript number, converts to real if integer

1.4. PostScript Level

Level 1 and later

1.5. Examples

Converting integer to real

42 cvr           % Result: 42.0
-17 cvr          % Result: -17.0

Real pass-through

3.14159 cvr      % Result: 3.14159 (unchanged)

String conversion

(123) cvr        % Result: 123.0
(3.14) cvr       % Result: 3.14
(1.5E2) cvr      % Result: 150.0

1.6. Common Use Cases

1.6.1. Ensuring Real Arithmetic

width cvr height cvr div  % Real division

1.6.2. Configuration Parsing

configfile readline {
  token { cvr /scale exch def } if
} if

1.7. Common Pitfalls

String Must Be Valid Number - String must contain valid PostScript number syntax.

(abc) cvr        % Error: syntaxerror

Use for Precision - Convert integers to reals before division to avoid integer truncation.

1.8. Error Conditions

Error	Condition
[invalidaccess]	String has no-access attribute
[limitcheck]	Number exceeds implementation limits
[stackunderflow]	No operand on stack
[syntaxerror]	String not valid number syntax
[typecheck]	Operand not number or string
[undefinedresult]	Invalid number in string

1.9. See Also

• cvi - Convert to integer

• cvs - Convert to string

• type - Get object type