= oup_id(df, cols=) Please see the documentation for group_id.Įgen newvar = (var), by(groupvar1 groupvar2)ĭf = df.groupby().transform(''). If you want a full constant column on your DataFrame, you can do df = 7 or whatever the constant is. NOTE: For theseĮgen commands, newvar is a full (constant) column in Stata, while it is a scalar in Python. Manipulate df.columns like a list: df.columns = ['a', The rows of df that don't meet the condition will be missingĭf = df.rename(columns=). Shift().fillna(0) even though the end result is the same. shift(fillna=0) is much, much slower than Issue with with larger data sets (usually several gigabytes). In IPython to easily test which one is faster. Sometimes, it doesn't matter which way you do it. This also means that sometimes there is more than one way to do things. It's like learningĪn alphabet with 26 letters and composing millions of words instead of learning Means that there are fewer base commands to learn in pandas. May annoying to type a few more characters, this is actually a good thing! It One-liner (for example, see Stata's drop varstem* below). Sometimes Python/pandas will require composed commands where Stata uses a In this way, you can create (i.e., "compose") new commands. This command doesn't have it's ownĭedicated if command. So let's say the second command you know is df.describe() which is theĮquivalent of Stata's summary. Now know the general if syntax for every other pandas That can be acted upon independently of df itself. in Stata, except df is itself a DataFrame First,ĭf, which returns the rows of DataFrame df for This is a little more difficult in Stata where each line of codeįor example, let's say you know two commands in Python/pandas. "composability." That is, you can combine base-level commands to "create" whole One concept that will push your Python skills forward quickly is Because of this, in Python represents a list Looking for a variable-a list, a number, a string-that's been defined If you were to write df without quotes, Python would go That in many cases, will be simple text in Stata (e.g.,Īvg_income) while in Python it will be a string ( 'avg_income'). show where user-specified values go in each language. The Stata-to-Python translations below are written assuming that you have a Variable just like in Stata, except that when you reference a column, you also You can think of each column in a DataFrame as a That a DataFrame is itself a variable and you can work with any number ofĭataFrames at one time. Where each column and each row has a name. The Pandas package implements a kind of variable called aĭataFrame that acts a lot like the single dataset in Stata. Variables can be anything, a single number, a matrix, a list, a Python is a general purpose programming language where a "variable" is not aĬolumn of data. The dataset is a matrix where eachĬolumn is a "variable" with a unique name and each row has a number (the In Stata, you have one dataset in memory. Mean.Coding in Python is a little different than coding in Stata. Let’s have a look at the helpįile for summarize. All the extra stuff aboutīy, if and in could be confusing. Understanding the overall syntax of Stata commands helps you remember them and use them more effectively, and it alsoĪids you understand the help files in Stata. General syntax of the summarize command can be described as: summarize, Summarize with complex if specifying records to summarize. Summarize with simple if specifying records to summarize. summarize mpg priceĪ range of records to be summarized. They are each presentedįor example, summarize followed by the names of variables. There are many parts that can come after a command. summarize mpg price if foreign = 1 & mpg foreign= 0Ī command can be preceded with a by prefix, as shown below. Here, we ask for summary statistics for the foreign cars which get less than 30 miles per gallon. The if qualifier can contain more than one condition. summarize mpg price if (foreign = 1) Variable | Obs Mean Std. We could further tell Stata to limit the summary statistics to just foreign cars by adding an if summarize mpg price Variable | Obs Mean Std. For example, below we get summary statistics just for mpg and It is also possible to obtain means for specific variables. sysuse autoĪs you have seen, we can type summarize and it will give us summary statistics for all of the variables We will demonstrate this using summarize as an example, although this general structure applies to most Stata commands. This module shows the general structure of Stata commands.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |