Character & Numeric Functions (Part-2)

SAS has another set of very important set of functions, which are used in preparation of data. These functions are numeric functions. Below is a table for some of the numeric function.

Numeric Functions:

Function	Application
Int (Variable_name)	Give integer part of variable
Round(Variable_name, rounding off value)	An rounded value of variable is returned
missing(Variable_name)	Return a '1' in case of variable has no value
n( of var1-var2)	Return no. of observations
n( variable1_name, variable2_name, ...)	Return count of non missing variable in same observations
min( of var1-varn)	return min. of variable values
max( of var1-varn)	return max. of variable values
mean(of var1-varn)	return mean of variable values
nmiss(of var1-varn)	return count of missing of variable values
largest( n, of var1-var10)	return nth order largest value like for n =2 second largest, n =3 third largest
abs(Variable_name)	Will return absolute value
sqrt(variable_name)	Will return square root of variable value
exp(variable_name)	Will return exponential
Lagn(variable)	Will return nth lagged value of variable
Ranuni (0)	Generates a random value between 0 & 1, which is based on unform distribution
diffn(variable_name)	Will return a difference of current value & nth lagged value for the variable

Now lets consider an example of a sales data of a grocery store as mentioned below.

 item_id          Cost         MRP       Disc.        

GR_012          32.05      41.54       5.05%

GR_121         29.45       32.45      6.97%

CP_312         12.21        15.65      7.23%

DN_121         6.43         7.12        1.05%

Now shopkeeper wants to calculate profit margin if he sells item on MRP & gives discount mentioned in the data. We will have to use a combination of character & numeric variable in order to achieve client's requirement.

Let's first bring this data into SAS.

DATA ITEM_DATA;

INPUT ITEM_ID$ COST MRP DISC$;

DATALINES;

GR_012 32.05 41.54 5.05%

GR_121 29.45 32.45 6.97%

CP_312 12.21 15.65 7.23%

DN_121 6.43 7.12 1.05%

;

RUN;

                                                                                                                                        

DATA ITEM_DATA1;                                                                                                                        

SET ITEM_DATA (RENAME=(DISC = DISCOUNT));                                                               

DISC = INPUT(COMPRESS(DISCOUNT,'%'),8.);                                                         

SELL_PRICE = (1- DISC/100)*MRP;                                                                                    

MARGIN = ROUND((SELL_PRICE - COST)*100/SELL_PRICE, 0.01); 

MARGIN_IN_PERCENT = CAT(PUT(MARGIN, 5.2), '%');                                                        

DROP DISCOUNT;                                                                                                                          

RUN;

There are so many things happening here in this code. I will explain all of them, one at a time. 

So as i said earlier also, SAS gives user a method to change a character variable into a numeric variable. Here we have discounts as character datatype. In order to calculate Selling price we have to convert discount into a numeric variable. An input function can be used to do so. We have used rename option to recover original name of the variable. An input statement has a character variable passed into first argument & then a format length modifier, which will tell SAS, in what format do we need this value. Here 8. is a numeric format having length of 8 bytes. We have also used a compress function to remove '%' sign from the discount variable. 

Now once we have disc in numeric format we can make calculations for Margin, Since most of the time we need a percent upto 2 decimal value we have used a Round function to convert a value into 2 decimal format.

To understand a numeric to character conversion, we have used margin variable & used a PUT function which will convert Margin_in_percent as character value. For future calculation purpose we can use Margin, which is still a numeric value.