The local command is a way of defining macro in stata. What command to use in stata to check if value in one variable is equal to any. Throughout, bold type will refer to stata commands, while le names, variables names, etc. We use the stata function substr in a gen command to extract the.
Actually, i am using a panel data, but unfortunately, many variables are considered as string. How to extract few letters of a string variable in stata. And i would like to use substring command to create a new variable take the. Lets take a brief moment to introduce stata to those who have never used it before. The graph command, in this example, displays a scatter plot of read and write along with showing the regression line of write on read. In this video i will explain some common applications of the substring function using visual basic 2010.
Stata is available on the pcs in the computer lab as well as on the unix system. Save space by quickly compressing stata files may 1, 20 computing, software stata ntjames stata has a nice function called compress which reduces the size of your dataset by demoting storage types, i. Stata is an interactive statistical graphics software package that contains a wide variety of statistical applications including some that are difficult at best to compute in other statistical software packages. And i guarantee you that your future self will be very happy. For example, you want to make a new variable and know you can use the assignment statement e.
I might be missing something simple, but stata results do not seem to paste easily into excel. The predict command computes a predicted science score for each observation. R has powerful indexing features for accessing object elements. There are five steps to using the replace statement. How to use substring command statalist the stata forum. Develop the ability to independently learn how to use commands in stata using help. This includes general program use and how to create do files. Dear all, i have a dataset which contain id number with the display format is %6. And equally naturally, much thought has been given by stata corporation and others to providing good solutions to this need to get to grips with stata easily and e. Say that you use sas but wish to know how to do a particular command in stata. Create a standalone sticky note app using indexed database api duration. For example, using the auto data set sysuse auto, clear 1978. Stata module to report number of unique values in variables, statistical software components s354201, boston college department of.
To create new variables typically from other variables in your data set, plus some arithmetic or logical expressions, or to modify variables that already exist in your data set, stata provides two versions of basically the same procedures. Understanding the substr command php tutorial youtube. Stata software can be used to calculate proportions and standard errors for nhanes data because the software takes into account the complex survey design of nhanes data when determining variance estimates. This may be a better way to go than doing the recodes yourself. To run code in stata, only the command is required, the other three parts are optional, however you will use them extensively. By using nsplit, the block of codes above can be shortened into a single line as follows. The following code snippets demonstrate ways to keep or delete variables and observations and to take random samples from a dataset. I tried to use the command destring, but stata tell me some characters are not numeric, which the numbers are written as follow. Using stata efficiently to understand your data the. Below that will typically be examples of using the command, including. The command to set the character that divides stata commands is.
I have a quick question regarding the substr command and generating a new variable. Command generate is used if a new variable is to be added to the data set. These features can be used to select and exclude variables and observations. Stata user should knoware strpos, substr, subinstr, and length. Here we introduce another command local, which is utilized a lot with commands like foreach to deal with repetitive tasks that are more complex. But we can do better by using the builtin function inlist. Learning a little bit more about statas builtin functions can be very convenient sometimes necessaryshorter codes, faster processing, more facebook time. What command can i use to select variables containing specific. Need help creating a variable using the substr command. Sep 30, 2012 each stata command was classified according to which reference manual its listed in.
Hi carmen, i am not familiar with these datasets, but help icd9 brings up the stata command icd9, which can generate new variables from existing icd9 codes. Memory in stata version 11 or earlier as of this writing, stata is in version 15. You need to combine the string function substr with other commands to extract the data. And i guarantee you that your future self will be very happy with your present self if you take the time to do this. Replace the replace command is more versatile than the recode command, but it requires more coding steps.
Save space by quickly compressing stata files do the stats. Oct 20, 2011 but we can do better by using the builtin function inlist. May 01, 20 save space by quickly compressing stata files may 1, 20 computing, software stata ntjames stata has a nice function called compress which reduces the size of your dataset by demoting storage types, i. Counting substrings within strings the stata journal. This variable has values such as 99sedan, 2002jeep, 20suv07, 1995coupe, 1998rv, etc. The stata command forvalues is a loop command which goes through all the variable prefixes in the data. This can be quite useful if you have commands that span more than one line, because it improves the readability of your code. You can do the same thing in one line by simply using the rename command.
Examples of the types of papers include 1 expository papers that link the use of stata commands or programs to associated principles, such as those that will. Hes not using a standardised metadata format like xml, json that has standard libraries and efficient methods for updating data. Jan 03, 2011 actually, i am using a panel data, but unfortunately, many variables are considered as string. You can access the pdf documentation by clicking on the blue text for example, d import or by using the menu. If you are using stata version 11 or earlier, and you will read in a big dataset, then before reading in your data you must tell stata to make available enough computer memory for. Panel data refers to data that follows a cross section over timefor example, a sample of individuals surveyed repeatedly for a number of years or data for all 50 states for all census years. I will demonstrate all of these commands in this lecture. Stata programs of interest either to a wide spectrum of users e.
Im frequently using stata to process data that needs to go into an existing excel template. And i would like to use substring command to create a new variable take the number before the dot. For example typing help gen in stata shows that gen is in manual d for data management. Each stata command was classified according to which reference manual its listed in. Sofware carpentry helping scientists make better software since. Figure 2 is the screenshot of a help file from stata for the regress command help. The analysis can be done by using mvprobit program in stata. I know it is quite easy to carry out it in r through dplyr package but i dont seem to find anything in stata. I run command files exclusively in everything i do. Say, we want to input the following table of data into stata.
Unlike decode, sdecode creates an output string variable containing the values of the input variable as output by the list command and other stata output, instead of decoding all unlabelled input values to missing. Diego expects stata to realise that he means substr with its argument, but stata is strong on syntax and weak on semantics. For a very long time i have used the string function substr to split all sorts of codes into components. Help and then pdf documentation stata syntax is consistent in general there is a command name followed by selection of variables. If you are new to stata we strongly recommend reading all the articles in the stata basics section. Type \help import stata documentation is extensive and outstanding. This seminar covers stata commands and methods to prepare data for statistical analysis. Stata acts like i hit break loops, input, stata this is a cute idea, but it is not workable.
Say in stata i created a frequency table with gender as the columns and ethnicity as the rows using tab ethnicity gender. In substrs, b, l and substrs, b, if b describes a position before the beginning of the string or after the end, is returned. This article is part of the stata for students series. Stata also has help files accessible through the main menu. This can be useful to add data that may not be used in the ensuing statistical analysis, such as graphing data. In this article youll learn how to create new variables and change existing variables. Review and cite stata software protocol, troubleshooting and other methodology information contact experts in stata software to get answers. To get this list, i pulled the stata commands from all the shared folders and classified the 100 most common commands download stataclass. When arguments are not scalar, substr returns elementbyelement results.
The help file for every stata command will tell you exactly how to use that command, including its syntax and if it allows ifstatements and what its options are. Note that inlist and substr, like regexs, are all functions, not commands. If there is a binary 0 to the right of b, the substring from b up to but not including the binary 0 is returned. Compare pre1 with pre2 that was created using the generate command.
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