isDigit

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Description

Analyse if a char is a digit (that is a number). Returns true if thisChar is a number.

Inclusion

• defined in misc.h
• auto-loaded in main_general.h
• no #define required

Syntax

isDigit(thisChar)

Parameters

• input:

  • thisChar: character to test (char)

• output:

  • none

Returns

• true: if thisChar is a number.
• false: otherwise

Example Code

The below code reads a char from the terminal and checks for isDigit().

#include "main_general.h"
#include "uart1.h"
#include "putchar.h"

void setup() {

  // init UART, printf() and gets()
  UART1_begin(115200);
  putcharAttach(UART1_write);

} // setup

void loop() {

  if (UART1_available())
    if (isDigit(UART1_read()))
      printf("isDigit(x) = true\n");
    else
      printf("isDigit(x) = false\n");

}

Relevant Tutorial

• tbd

See also

• isAlpha()
• isAlphaNumeric()
• isAscii()
• isControl()
• isGraph()
• isHexadecimalDigit()
• isLowerCase()
• isPrintable()
• isPunct()
• isSpace()
• isUpperCase()
• isWhitespace()