strcpy in c language

#include <stdio.h>
#include <string.h>


int main()
{
    char str1[10]= "hello";
    char str2[10];
    char str3[10];
    strcpy(str2, str1);
    strcpy(str3, "world");
    puts(str2);
    puts(str3);
    return 0;
}

strncpy example in c language

/* strncpy example */
#include <stdio.h>
#include <string.h>

int main ()
{
  char str1[]= "To be or not to be";
  char str2[40];
  char str3[40];

  /* copy to sized buffer (overflow safe): */
  strncpy ( str2, str1, sizeof(str2) );

  /* partial copy (only 5 chars): */
  strncpy ( str3, str2, 5 );
  str3[5] = '\0';   /* null character manually added */

  puts (str1);
  puts (str2);
  puts (str3);

  return 0;
}

memcpy function in C language

/* A C program to demonstrate working of memcpy */
#include <stdio.h>
#include <string.h>

int main ()
{
char str1[] = "Geeks";
char str2[] = "Quiz";

puts("str1 before memcpy ");
puts(str1);

/* Copies contents of str2 to sr1 */
memcpy (str1+5, str2, sizeof(str2));

puts("\nstr1 after memcpy ");
puts(str1);

return 0;
}

memset example in c program

// C program to demonstrate working of memset()
#include <stdio.h>
#include <string.h>

int main()
{
    char str[50] = "GeeksForGeeks is for programming geeks.";
    printf("\nBefore memset(): %s\n", str);

    // Fill 8 characters starting from str[13] with '.'
    memset(str + 13, '*', 8*sizeof(char));

    printf("After memset():  %s", str);
    return 0;
}




https://drive.google.com/file/d/1xYaDVv94E0CW72A67l5umgmtn1NDT5J2/view?usp=sharing

stm32 uart communication working code

stm32 uart communication working code

STM32F103XX UART COMMUNICATION

/* USER CODE BEGIN Header */

/**

  ******************************************************************************

  * @file           : main.c

  * @brief          : Main program body

  ******************************************************************************

  * @attention

  *

  * <h2><center>&copy; Copyright (c) 2019 STMicroelectronics.

  * All rights reserved.</center></h2>

  *

  * This software component is licensed by ST under BSD 3-Clause license,

  * the "License"; You may not use this file except in compliance with the

  * License. You may obtain a copy of the License at:

  *                        opensource.org/licenses/BSD-3-Clause

  *

  ******************************************************************************

  */

/* USER CODE END Header */

/* Includes ------------------------------------------------------------------*/

#include "main.h"

#include "usart.h"

#include "gpio.h"

/* Private includes ----------------------------------------------------------*/

/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/

/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/

/* USER CODE BEGIN PD */

/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/

/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/

void SystemClock_Config(void);

/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**

  * @brief  The application entry point.

  * @retval int

  */

int main(void)

{

  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */

  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */

  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */

  MX_GPIO_Init();

  MX_USART1_UART_Init();

  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

  /* Infinite loop */

  /* USER CODE BEGIN WHILE */

  while (1)

  {

    /* USER CODE END WHILE */

HAL_UART_Transmit(&huart1,"hello\n",10,100);

HAL_Delay(1000);

    /* USER CODE BEGIN 3 */

  }

  /* USER CODE END 3 */

}

/**

  * @brief System Clock Configuration

  * @retval None

  */

void SystemClock_Config(void)

{

  RCC_OscInitTypeDef RCC_OscInitStruct = {0};

  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Initializes the CPU, AHB and APB busses clocks 

  */

  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;

  RCC_OscInitStruct.HSIState = RCC_HSI_ON;

  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;

  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;

  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)

  {

    Error_Handler();

  }

  /** Initializes the CPU, AHB and APB busses clocks 

  */

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK

                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;

  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;

  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;

  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;

  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)

  {

    Error_Handler();

  }

}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**

  * @brief  This function is executed in case of error occurrence.

  * @retval None

  */

void Error_Handler(void)

{

  /* USER CODE BEGIN Error_Handler_Debug */

  /* User can add his own implementation to report the HAL error return state */

  /* USER CODE END Error_Handler_Debug */

}

#ifdef  USE_FULL_ASSERT

/**

  * @brief  Reports the name of the source file and the source line number

  *         where the assert_param error has occurred.

  * @param  file: pointer to the source file name

  * @param  line: assert_param error line source number

  * @retval None

  */

void assert_failed(uint8_t *file, uint32_t line)

{ 

  /* USER CODE BEGIN 6 */

  /* User can add his own implementation to report the file name and line number,

     tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

  /* USER CODE END 6 */

}

#endif /* USE_FULL_ASSERT */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

sample calculator using simple gui tkinter in python

""" ***********************************************
programming Language :Python
Tool(IDE) used :Anaconda -> Spider
 date:03-07-2019
 created by:ANIL DURGAM

*****************************************************"""
# Python program to create a simple GUI

# calculator using Tkinter

# import everything from tkinter module

from tkinter import *


# globally declare the expression variable

expression = ""


# Function to update expressiom

# in the text entry box

def press(num):

 # point out the global expression variable

 global expression

 # concatenation of string

 expression = expression + str(num)
 # update the expression by using set method

 equation.set(expression)
# Function to evaluate the final expression

def equalpress():

 # Try and except statement is used

 # for handling the errors like zero

 # division error etc.

 # Put that code inside the try block

 # which may generate the error

 try:

  global expression

  # eval function evaluate the expression

  # and str function convert the result

  # into string

  total = str(eval(expression))



  equation.set(total)



  # initialze the expression variable

  # by empty string

  expression = ""

 # if error is generate then handle

 # by the except block

 except:

  equation.set(" error ")

  expression = ""

# Function to clear the contents

# of text entry box

def clear():

 global expression

 expression = ""

 equation.set("")

# Driver code

if __name__ == "__main__":

 # create a GUI window

 gui = Tk()
 # set the background colour of GUI window

 gui.configure(background="light green")
 # set the title of GUI window

 gui.title("Simple Calculator")
 # set the configuration of GUI window

 #gui.geometry("265x125")
 gui.geometry("360x180")

 # StringVar() is the variable class

 # we create an instance of this class

 equation = StringVar()
 # create the text entry box for

 # showing the expression .

 expression_field = Entry(gui, textvariable=equation)
 # grid method is used for placing

 # the widgets at respective positions

 # in table like structure .

 expression_field.grid(columnspan=4, ipadx=80)

 equation.set('enter your expression')

 # create a Buttons and place at a particular

 # location inside the root window .

 # when user press the button, the command or

 # function affiliated to that button is executed .

 button1 = Button(gui, text=' 1 ', fg='black', bg='white',

     command=lambda: press(1), height=1, width=7)

 button1.grid(row=2, column=0)



 button2 = Button(gui, text=' 2 ', fg='black', bg='white',

     command=lambda: press(2), height=1, width=7)

 button2.grid(row=2, column=1)



 button3 = Button(gui, text=' 3 ', fg='black', bg='white',

     command=lambda: press(3), height=1, width=7)

 button3.grid(row=2, column=2)



 button4 = Button(gui, text=' 4 ', fg='black', bg='white',

     command=lambda: press(4), height=1, width=7)

 button4.grid(row=3, column=0)



 button5 = Button(gui, text=' 5 ', fg='black', bg='white',

     command=lambda: press(5), height=1, width=7)

 button5.grid(row=3, column=1)



 button6 = Button(gui, text=' 6 ', fg='black', bg='white',

     command=lambda: press(6), height=1, width=7)

 button6.grid(row=3, column=2)



 button7 = Button(gui, text=' 7 ', fg='black', bg='white',

     command=lambda: press(7), height=1, width=7)

 button7.grid(row=4, column=0)



 button8 = Button(gui, text=' 8 ', fg='black', bg='white',

     command=lambda: press(8), height=1, width=7)

 button8.grid(row=4, column=1)



 button9 = Button(gui, text=' 9 ', fg='black', bg='white',

     command=lambda: press(9), height=1, width=7)

 button9.grid(row=4, column=2)



 button0 = Button(gui, text=' 0 ', fg='black', bg='white',

     command=lambda: press(0), height=1, width=7)

 button0.grid(row=5, column=0)



 plus = Button(gui, text=' + ', fg='black', bg='white',

    command=lambda: press("+"), height=1, width=7)

 plus.grid(row=2, column=3)



 minus = Button(gui, text=' - ', fg='black', bg='white',

    command=lambda: press("-"), height=1, width=7)

 minus.grid(row=3, column=3)



 multiply = Button(gui, text=' * ', fg='black', bg='white',

     command=lambda: press("*"), height=1, width=7)

 multiply.grid(row=4, column=3)



 divide = Button(gui, text=' / ', fg='black', bg='white',

     command=lambda: press("/"), height=1, width=7)

 divide.grid(row=5, column=3)



 equal = Button(gui, text=' = ', fg='black', bg='white',

    command=equalpress, height=1, width=7)

 equal.grid(row=5, column=2)



 clear = Button(gui, text='Clear', fg='black', bg='white',

    command=clear, height=1, width=7)

 clear.grid(row=5, column='1')



 # start the GUI

 gui.mainloop()



output:

python interview questions part 1

Question 1:
x = 6
print(6)
print("6")
what is the out put for the above code??

Question 2:

value1 = eval(input('Please enter a number: '))
value2 = eval(input('Please enter another number: '))
sum = value1 + value2
print(value1, '+', value2, '=', sum)

what is output for the above code??


Question 3:

print(10/3, 3/10, 10//3, 3//10)

out put of the above print??

input function in python

""" ***********************************************
programming Language :Python
Tool(IDE) used :Anaconda -> Spider
 date:06-06-2019
 created by:ANIL DURGAM

*****************************************************"""
print('Please enter an integer value:')
x = input()
print('Please enter another integer value:')
y = input()
num1 = int(x)
num2 = int(y)
print(num1, '+', num2, '=', num1 + num2)

output:
Please enter an integer value:

25
Please enter another integer value:

52
25 + 52 = 77

typed function use in python

print('Please enter some text:')
x = input()
print('Text entered:', x)
print('Type:', type(x))

output:
Please enter some text:

anil
Text entered: anil
Type: <class 'str'>



type is used for find the catagory of the given input

Importing functions from a module in python

Importing functions from a module
Three ways to import functions:
1.
the simplest way: import everything from a module
advantage: simple usage e.g. of math functions
disadvantage: risk of naming conflicts when a variable has the same name as a module function
from numpy import *
print sin(pi/4)
# With this import method the following would give an error:
#sin = 5 # naming conflict!
#print sin(pi/4)
2.
import module under an alias name that is short enough to enhance code clarity
advantage: it is clear to see which function belongs to which module
import numpy as np
print np.sin(np.pi/4)
3.
import only the functions that are needed
advantage: simple usage e.g. of math functions
naming conflict possible, but less probable than with 1.
disadvantage: you must keep track of all the used functions and adapt the import statement if a
new function is used
from numpy import linspace, sin, exp, pi
print sin(pi/4)