The ReadFloat(file) command attempts to read a float from file.  The ReadFloat command skips whitespace until an integer or non-whitespace character is found.  If there is a valid float, it is read from file and returned.  If the characters do not form a valid float, then NULL is returned.

If no float is found, the file position is reset to its value before the call to ReadFloat was made.

To determine if the end of the file has been reached, use AtEndOfFile.

If file is the name of a file that has not been opened, Maple attempts to open the file before reading the float.

An error is raised if file is not a valid descriptor or if it is the name of a file that has not been opened.