# Input

Input Variables
The input storage class defines the external variable. The input modifier is indicated before the data type. A variable with the input modifier can't be changed inside mql4-programs, such variables can be accessed for reading only. Values of input variables can be changed only by a user from the program properties window. External variables are always reinitialized immediately before the OnInit() is called.

Example:

//--- input parameters
input int            MA_Period=13;
input int            MA_Shift=0;
input ENUM_MA_METHOD MA_Method=MODE_SMMA;

There is another way to set how your input parameter will look like in the Inputs tab. For this, place a string comment after the description of an input parameter in the same line. In this way you can make names of input parameters more understandable for users.

//--- input parameters
input int            InpMAPeriod=13;         // Smoothing period
input int            InpMAShift=0;           // Line horizontal shift
input ENUM_MA_METHOD InpMAMethod=MODE_SMMA;  // Smoothing method

input ENUM_MA_METHOD MAMethod = MODE_EMA;

//
// Gives time frame as an input ...
input ENUM_TIMEFRAMES Timeframe = PERIOD_CURRENT;


in adding input data to your advisors, indicators or etc, you can groups your input's together.
for this following below descriptions:

int group "Moving Avarage Filter"

every inputs appears after this, attached to created group ...