astChr2DoubleastChr2Double - read a double value from a string

Description:
This function reads a double from the supplied null-terminated string, ignoring leading and trailing white space. AST__BAD is ereturned without error if the string is not a numerical value.
Synopsis:
double astChr2Double( const char $*$str )
Parameters:
str
Pointer to the string.
Returned Value:
astChr2Double()
The double value, or AST__BAD.
Notes:
  • A value of AST__BAD is returned if this function is invoked with the global error status set or if it should fail for any reason.