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| In the topic of data formats in Stata, the concept of '''display formats''' is of primary interest. Stata uses display formats to extend the [[Stata/DataTypes|type system]]. | The Stata data file format encodes variable metadata including '''display formats'''. While these formats primarily affect visualization, they can also encode critical information about how a variable should be used. |
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| Several commands have internal ideas about data formats. | See also the underlying [[Stata/DataTypes|data types]]. |
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| A display format is set like: {{{ generate double my_datetime = clock(some_string, "YMDhms") format my_datetime %tc }}} ---- |
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| The ''default'' display format for each numeric data type is as follows: | For the most part, all numeric types operate the same way in Stata. See [[Stata/NumericFunctions|Numeric Functions]] for operating on this type of data. Each underlying numeric data format applies a different display format by default. They are: |
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| The ''available'' numeric formats are '''`e`''', '''`f`''', and '''`g`'''. The '''general format''' (`g`) indicates that the number of decimal places should be shifted to improve readability. The '''fixed width format''' (`f`) indicates that a fixed number of decimal places should be shown. The '''scientific format''' (`e`) indicates that scientific notation should be used. | The available numeric formats are: * '''general format''' (`g`) indicating that the number of decimal places should be shifted to improve readability * '''fixed width format''' (`f`) indicating that a fixed number of decimal places should be shown * '''scientific format''' (`e`) indicating that scientific notation should be used As an example: |
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| A `c` can be appended to any numeric format to indicate that commas should be shown. | A `c` can be appended to any numeric format to display commas. ---- |
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| Dates and datetimes are numeric data with unit-specific display formats. These are: | Dates and datetimes are numeric data with a standardized, encoded meaning. The display format is what indicates the intended encoding. For the most part, this type of data counts days or milliseconds from the Stata epoch: `01jan1960 00:00:00.000`. See [[Stata/DatetimeFunctions|Datetime Functions]] for operating on this type of data. Specifically, the date and datetime formats are: |
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| These formats can be customized with specific components. | These formats can be further customized, for visualization purposes only, with specific components. |
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| ||'''Component'''||'''Specification'''||'''Displays As'''|| ||Century ||`CC` ||`01` || ||Century ||`cc` ||`1` || ||Year ||`YY` ||`01` || ||Year ||`yy` ||`1` || |
||'''Component''' ||'''Specification'''||'''Displays As''' || ||Century ||`CC` ||`01`-`99` || ||Century ||`cc` ||`1`-`99` || ||Year ||`YY` ||`01`-`99` || ||Year ||`yy` ||`1`-`99` || ||Day of year ||`JJJ` ||`001`-`366` || ||Day of year ||`jjj` ||`1`-`366` || ||Month ||`Mon` ||`Jan`-`Dec` || ||Month ||`Month` ||`January`-`December` || ||Month ||`mon` ||`jan`-`dec` || ||Month ||`month` ||`january`-`december` || ||Month ||`NN` ||`01`-`12` || ||Month ||`nn` ||`1`-`12` || ||Day ||`DD` ||`01`-`31` || ||Day ||`dd` ||`1`-`31` || ||Day of week ||`DAYNAME` ||`Sunday`-`Saturday` (aligned) || ||Day of week ||`Dayname` ||`Sunday`-`Saturday` (unaligned)|| ||Day of week ||`Day` ||`Sun`-`Sat` || ||Day of week ||`Da` ||`Su`-`Sa` || ||Day of week ||`day` ||`sun`-`sat` || ||Day of week ||`da` ||`su`-`sa` || ||Half-year ||`h` ||`1` or `2` || ||Quarter ||`q` ||`1`-`4` || ||Week ||`WW` ||`01`-`52` || ||Week ||`ww` ||`1`-`52` || ||Hour ||`HH` ||`00`-`23` || ||Hour ||`Hh` ||`00`-`12` || ||Hour ||`hH` ||`0`-`23` || ||Hour ||`hh` ||`0`-`12` || ||Minute ||`MM` ||`00`-`59` || ||Minute ||`mm` ||`0`-`59` || ||Second ||`SS` ||`00`-`60` (due to leap second) || ||Second ||`ss` ||`0`-`60` (due to leap second) || ||Tenths ||`.s` ||`.0`-`.9` || ||Hundredths ||`.ss` ||`.00`-`.99` || ||Thousandths ||`.sss` ||`.000`-`.999` || ||AM/PM ||`am`/`pm` ||`am` or `pm` || ||AM/PM ||`a.m.`/`p.m.` ||`a.m.` or `p.m.` || ||AM/PM ||`AM`/`PM` ||`AM` or `PM` || ||AM/PM ||`A.M.`/`P.M.` ||`A.M.` or `P.M.` || ||Period ||`.` ||`.` || ||Comma ||`,` ||`,` || ||Colon ||`:` ||`:` || ||Hyphen ||`-` ||`-` || ||Space ||` ` ||` ` || ||Forward slash ||`/` ||`/` || ||Back slash ||`\` ||`\` || ||Literal character||`!c` ||`c` || |
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| A plus sign (`+`) can optionally delimit components for human readability. It is ignored otherwise. | |
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| JJJ day within year 001–366 jjj day within year 1–366 Mon month Jan, Feb, . . . , Dec Month month January, February, . . . , December mon month jan, feb, . . . , dec month month january, february, . . . , december NN month 01–12 nn month 1–12 DD day within month 01–31 dd day within month 1–31 DAYNAME day of week Sunday, Monday, . . . (aligned) Dayname day of week Sunday, Monday, . . . (unaligned) Day day of week Sun, Mon, . . . Da day of week Su, Mo, . . . day day of week sun, mon, . . . da day of week su, mo, . . . Datetime display formats — Display formats for dates and times 3 h half 1–2 q quarter 1–4 WW week 01–52 ww week 1–52 HH hour 00–23 Hh hour 00–12 hH hour 0–23 hh hour 0–12 MM minute 00–59 mm minute 0–59 SS second 00–60 (sic, due to leap seconds) ss second 0–60 (sic, due to leap seconds) .s tenths .0–.9 .ss hundredths .00–.99 .sss thousandths .000–.999 am show am or pm am or pm a.m. show a.m. or p.m. a.m. or p.m. AM show AM or PM AM or PM A.M. show A.M. or P.M. A.M. or P.M. . display period . , display comma , : display colon : - display hyphen - display space / display slash / \ display backslash \ !c display character c + separator Note: + displays nothing; it may be used to separate one code from the next to make the format more readable. + is never necessary. For instance, %tchh:MM+am and %tchh:MMam have the same meaning, as does %tc+hh+:+MM+am. |
---- |
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| == List == | == See also == |
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| The '''`list`''' command resizes and reformats output to try and maximize accessibility. This involves automated truncation and alignment overriding display formats. For information on formatting the output of `lists`, see [[Stata/List#Data_Formats|here]]. | [[https://www.stata.com/manuals/ddatetime.pdf|Stata datetimes]] |
Stata Data Formats
The Stata data file format encodes variable metadata including display formats. While these formats primarily affect visualization, they can also encode critical information about how a variable should be used.
See also the underlying data types.
Contents
Display Formats
A display format is set like:
generate double my_datetime = clock(some_string, "YMDhms") format my_datetime %tc
Numeric Formats
For the most part, all numeric types operate the same way in Stata.
See Numeric Functions for operating on this type of data.
Each underlying numeric data format applies a different display format by default. They are:
Type |
Format |
double |
%10.0g |
float |
%9.0g |
long |
%12.0g |
int |
%8.0g |
byte |
%8.0g |
The available numeric formats are:
general format (g) indicating that the number of decimal places should be shifted to improve readability
fixed width format (f) indicating that a fixed number of decimal places should be shown
scientific format (e) indicating that scientific notation should be used
As an example:
Value |
With format %9.4g |
With format %9.4f |
With format %9.2e |
3.14159 |
3.142 |
3.14 |
3.14e+00 |
314.159 |
314.2 |
314.16 |
3.14e+02 |
A c can be appended to any numeric format to display commas.
Date and Datetime Formats
Dates and datetimes are numeric data with a standardized, encoded meaning. The display format is what indicates the intended encoding. For the most part, this type of data counts days or milliseconds from the Stata epoch: 01jan1960 00:00:00.000.
See Datetime Functions for operating on this type of data.
Specifically, the date and datetime formats are:
Format |
Unit |
%tc |
milliseconds ignoring leap seconds |
%tC |
milliseconds with leap seconds |
%td |
days |
%tw |
weeks |
%tm |
months |
%tq |
quarters |
%th |
half-years |
%ty |
years |
These formats can be further customized, for visualization purposes only, with specific components.
Component |
Specification |
Displays As |
Century |
CC |
01-99 |
Century |
cc |
1-99 |
Year |
YY |
01-99 |
Year |
yy |
1-99 |
Day of year |
JJJ |
001-366 |
Day of year |
jjj |
1-366 |
Month |
Mon |
Jan-Dec |
Month |
Month |
January-December |
Month |
mon |
jan-dec |
Month |
month |
january-december |
Month |
NN |
01-12 |
Month |
nn |
1-12 |
Day |
DD |
01-31 |
Day |
dd |
1-31 |
Day of week |
DAYNAME |
Sunday-Saturday (aligned) |
Day of week |
Dayname |
Sunday-Saturday (unaligned) |
Day of week |
Day |
Sun-Sat |
Day of week |
Da |
Su-Sa |
Day of week |
day |
sun-sat |
Day of week |
da |
su-sa |
Half-year |
h |
1 or 2 |
Quarter |
q |
1-4 |
Week |
WW |
01-52 |
Week |
ww |
1-52 |
Hour |
HH |
00-23 |
Hour |
Hh |
00-12 |
Hour |
hH |
0-23 |
Hour |
hh |
0-12 |
Minute |
MM |
00-59 |
Minute |
mm |
0-59 |
Second |
SS |
00-60 (due to leap second) |
Second |
ss |
0-60 (due to leap second) |
Tenths |
.s |
.0-.9 |
Hundredths |
.ss |
.00-.99 |
Thousandths |
.sss |
.000-.999 |
AM/PM |
am/pm |
am or pm |
AM/PM |
a.m./p.m. |
a.m. or p.m. |
AM/PM |
AM/PM |
AM or PM |
AM/PM |
A.M./P.M. |
A.M. or P.M. |
Period |
. |
. |
Comma |
, |
, |
Colon |
: |
: |
Hyphen |
- |
- |
Space |
|
|
Forward slash |
/ |
/ |
Back slash |
\ |
\ |
Literal character |
!c |
c |
A plus sign (+) can optionally delimit components for human readability. It is ignored otherwise.
String Formats
Alignment is controlled by the presence or absence of a negative sign (-) ahead of the width. A string variable formatted as %-18s will be left-justified; with a format of %18s it would have been right-justified.