output
All the examples below use the same standard data set that comes with Stata.
. sysuse auto, clear
(1978 Automobile Data)
Example 1
Serializing a single record
This method is currently exhibiting unanticipated behavior. The correct data is returned in the pay load, but the call is also returning multiple internal objects that may not be necessary/useful for most end users.
. jsonio out, what(record) obid(74)
{
"metaob" : {
"stataobs" : {
"iterator" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 5
> 9, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74 ],
"nobs" : 74,
"sobs" : 1,
"observationIndex" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 5
> 7, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74 ],
"eobs" : 74
},
"statavars" : {
"nvars" : 12,
"valueLabelNames" : {
"foreign" : "origin"
},
"valueLabels" : {
"foreign" : {
"0" : "Domestic",
"1" : "Foreign"
}
},
"variableIndex" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ],
"variableTypes" : {
"mpg" : false,
"price" : false,
"headroom" : false,
"rep78" : false,
"length" : false,
"weight" : false,
"displacement" : false,
"turn" : false,
"trunk" : false,
"make" : true,
"gear_ratio" : false,
"foreign" : false
},
"varIndexObject" : {
"name" : "variable index",
"values" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ],
"varIndexValues" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ]
},
"nvarsObject" : {
"name" : "number of variabels",
"values" : 12
},
"varNamesObject" : {
"name" : "Variable Names",
"iterator" : [ "make", "price", "mpg", "rep78", "headroom", "trunk", "weight", "length", "turn", "displacement", "gear_ratio", "foreign" ],
"values" : [ "make", "price", "mpg", "rep78", "headroom", "trunk", "weight", "length", "turn", "displacement", "gear_ratio", "foreign" ]
},
"varLabelsObject" : {
"name" : "Variable Labels",
"iterator" : [ "mpg", "price", "headroom", "rep78", "length", "weight", "displacement", "turn", "trunk", "make", "gear_ratio", "foreign" ],
"values" : {
"mpg" : "Mileage (mpg)",
"price" : "Price",
"headroom" : "Headroom (in.)",
"rep78" : "Repair Record 1978",
"length" : "Length (in.)",
"weight" : "Weight (lbs.)",
"displacement" : "Displacement (cu. in.)",
"turn" : "Turn Circle (ft.) ",
"trunk" : "Trunk space (cu. ft.)",
"make" : "Make and Model",
"gear_ratio" : "Gear Ratio",
"foreign" : "Car type"
}
},
"valLabNamesObject" : {
"name" : "Variable Label Names",
"iterator" : [ "foreign" ],
"values" : {
"foreign" : "origin"
}
},
"valLabelsObject" : {
"name" : "Value Labels",
"iterator" : [ "foreign" ],
"values" : {
"foreign" : {
"0" : "Domestic",
"1" : "Foreign"
}
}
},
"varTypesObject" : {
"name" : "String Variable Indicator",
"iterator" : [ "mpg", "price", "headroom", "rep78", "length", "weight", "displacement", "turn", "trunk", "make", "gear_ratio", "foreign" ],
"values" : {
"mpg" : false,
"price" : false,
"headroom" : false,
"rep78" : false,
"length" : false,
"weight" : false,
"displacement" : false,
"turn" : false,
"trunk" : false,
"make" : true,
"gear_ratio" : false,
"foreign" : false
}
},
"variableLabels" : {
"mpg" : "Mileage (mpg)",
"price" : "Price",
"headroom" : "Headroom (in.)",
"rep78" : "Repair Record 1978",
"length" : "Length (in.)",
"weight" : "Weight (lbs.)",
"displacement" : "Displacement (cu. in.)",
"turn" : "Turn Circle (ft.) ",
"trunk" : "Trunk space (cu. ft.)",
"make" : "Make and Model",
"gear_ratio" : "Gear Ratio",
"foreign" : "Car type"
},
"variableNames" : [ "make", "price", "mpg", "rep78", "headroom", "trunk", "weight", "length", "turn", "displacement", "gear_ratio", "foreign" ]
},
"varindex" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ],
"obsindex" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
> 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74 ],
"obs13" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60
> , 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74 ],
"obs14" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60
> , 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74 ],
"varNames" : [ "make", "price", "mpg", "rep78", "headroom", "trunk", "weight", "length", "turn", "displacement", "gear_ratio", "foreign" ],
"areStrings" : {
"mpg" : false,
"price" : false,
"headroom" : false,
"rep78" : false,
"length" : false,
"weight" : false,
"displacement" : false,
"turn" : false,
"trunk" : false,
"make" : true,
"gear_ratio" : false,
"foreign" : false
},
"variableLabels" : {
"mpg" : "Mileage (mpg)",
"price" : "Price",
"headroom" : "Headroom (in.)",
"rep78" : "Repair Record 1978",
"length" : "Length (in.)",
"weight" : "Weight (lbs.)",
"displacement" : "Displacement (cu. in.)",
"turn" : "Turn Circle (ft.) ",
"trunk" : "Trunk space (cu. ft.)",
"make" : "Make and Model",
"gear_ratio" : "Gear Ratio",
"foreign" : "Car type"
},
"valueLabelNames" : {
"foreign" : "origin"
}
},
"obid" : 74,
"name" : "DataRecord",
"data" : {
"mpg" : 17.0,
"price" : 11995.0,
"headroom" : 2.5,
"rep78" : 5.0,
"length" : 193.0,
"weight" : 3170.0,
"displacement" : 163.0,
"turn" : 37.0,
"trunk" : 14.0,
"make" : "Volvo 260",
"gear_ratio" : 2.9800000190734863,
"foreign" : 1.0
}
}
Example 2
Serialize all records that satisfy a given condition
. jsonio out if rep78 == 1, what(data)
{
"source" : "/Applications/Stata/ado/base/a/auto.dta",
"name" : "DataSet",
"data" : [ {
"mpg" : 24.0,
"price" : 4195.0,
"headroom" : 2.0,
"rep78" : 1.0,
"length" : 180.0,
"weight" : 2730.0,
"displacement" : 151.0,
"turn" : 40.0,
"trunk" : 10.0,
"make" : "Olds Starfire",
"gear_ratio" : 2.7300000190734863,
"foreign" : 0.0
}, {
"mpg" : 18.0,
"price" : 4934.0,
"headroom" : 1.5,
"rep78" : 1.0,
"length" : 198.0,
"weight" : 3470.0,
"displacement" : 231.0,
"turn" : 42.0,
"trunk" : 7.0,
"make" : "Pont. Firebird",
"gear_ratio" : 3.0799999237060547,
"foreign" : 0.0
} ]
}
Example 3
Serialize all data and meta data for records 71 - 74
. jsonio out in 71/74, w(all)
{
"values" : [ {
"mpg" : 41.0,
"price" : 5397.0,
"headroom" : 3.0,
"rep78" : 5.0,
"length" : 155.0,
"weight" : 2040.0,
"displacement" : 90.0,
"turn" : 35.0,
"trunk" : 15.0,
"make" : "VW Diesel",
"gear_ratio" : 3.7799999713897705,
"foreign" : 1.0
}, {
"mpg" : 25.0,
"price" : 4697.0,
"headroom" : 3.0,
"rep78" : 4.0,
"length" : 155.0,
"weight" : 1930.0,
"displacement" : 89.0,
"turn" : 35.0,
"trunk" : 15.0,
"make" : "VW Rabbit",
"gear_ratio" : 3.7799999713897705,
"foreign" : 1.0
}, {
"mpg" : 25.0,
"price" : 6850.0,
"headroom" : 2.0,
"rep78" : 4.0,
"length" : 156.0,
"weight" : 1990.0,
"displacement" : 97.0,
"turn" : 36.0,
"trunk" : 16.0,
"make" : "VW Scirocco",
"gear_ratio" : 3.7799999713897705,
"foreign" : 1.0
}, {
"mpg" : 17.0,
"price" : 11995.0,
"headroom" : 2.5,
"rep78" : 5.0,
"length" : 193.0,
"weight" : 3170.0,
"displacement" : 163.0,
"turn" : 37.0,
"trunk" : 14.0,
"make" : "Volvo 260",
"gear_ratio" : 2.9800000190734863,
"foreign" : 1.0
} ],
"firstRecordId" : 71,
"lastRecordId" : 74,
"variableIndices" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ],
"variableIsString" : {
"mpg" : false,
"price" : false,
"headroom" : false,
"rep78" : false,
"length" : false,
"weight" : false,
"displacement" : false,
"turn" : false,
"trunk" : false,
"make" : true,
"gear_ratio" : false,
"foreign" : false
},
"variableNames" : [ "make", "price", "mpg", "rep78", "headroom", "trunk", "weight", "length", "turn", "displacement", "gear_ratio", "foreign" ],
"variableLabels" : {
"mpg" : "Mileage (mpg)",
"price" : "Price",
"headroom" : "Headroom (in.)",
"rep78" : "Repair Record 1978",
"length" : "Length (in.)",
"weight" : "Weight (lbs.)",
"displacement" : "Displacement (cu. in.)",
"turn" : "Turn Circle (ft.) ",
"trunk" : "Trunk space (cu. ft.)",
"make" : "Make and Model",
"gear_ratio" : "Gear Ratio",
"foreign" : "Car type"
},
"valueLabelNames" : {
"foreign" : "origin"
},
"valueLabels" : {
"foreign" : {
"0" : "Domestic",
"1" : "Foreign"
}
},
"numberOfRecords" : 4,
"numberOfVariables" : 12
}
Example 4
Serialize all data and metadata for the dataset in memory
. jsonio out, w(all)
{
"values" : [ {
"mpg" : 22.0,
"price" : 4099.0,
"headroom" : 2.5,
"rep78" : 3.0,
"length" : 186.0,
"weight" : 2930.0,
"displacement" : 121.0,
"turn" : 40.0,
"trunk" : 11.0,
"make" : "AMC Concord",
"gear_ratio" : 3.5799999237060547,
"foreign" : 0.0
}, {
...
}, {
"mpg" : 17.0,
"price" : 11995.0,
"headroom" : 2.5,
"rep78" : 5.0,
"length" : 193.0,
"weight" : 3170.0,
"displacement" : 163.0,
"turn" : 37.0,
"trunk" : 14.0,
"make" : "Volvo 260",
"gear_ratio" : 2.9800000190734863,
"foreign" : 1.0
} ],
"firstRecordId" : 1,
"lastRecordId" : 74,
"variableIndices" : [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ],
"variableIsString" : {
"mpg" : false,
"price" : false,
"headroom" : false,
"rep78" : false,
"length" : false,
"weight" : false,
"displacement" : false,
"turn" : false,
"trunk" : false,
"make" : true,
"gear_ratio" : false,
"foreign" : false
},
"variableNames" : [ "make", "price", "mpg", "rep78", "headroom", "trunk", "weight", "length", "turn", "displacement", "gear_ratio", "foreign" ],
"variableLabels" : {
"mpg" : "Mileage (mpg)",
"price" : "Price",
"headroom" : "Headroom (in.)",
"rep78" : "Repair Record 1978",
"length" : "Length (in.)",
"weight" : "Weight (lbs.)",
"displacement" : "Displacement (cu. in.)",
"turn" : "Turn Circle (ft.) ",
"trunk" : "Trunk space (cu. ft.)",
"make" : "Make and Model",
"gear_ratio" : "Gear Ratio",
"foreign" : "Car type"
},
"valueLabelNames" : {
"foreign" : "origin"
},
"valueLabels" : {
"foreign" : {
"0" : "Domestic",
"1" : "Foreign"
}
},
"numberOfRecords" : 74,
"numberOfVariables" : 12
}
Example 5
Serialize selected variables for observations satisfying a given condition
. jsonio out mpg weight price make if rep78 == 1, w(data)
{
"source" : "/Applications/Stata/ado/base/a/auto.dta",
"name" : "DataSet",
"data" : [ {
"mpg" : 24.0,
"price" : 4195.0,
"weight" : 2730.0,
"make" : "Olds Starfire"
}, {
"mpg" : 18.0,
"price" : 4934.0,
"weight" : 3470.0,
"make" : "Pont. Firebird"
} ]
}
Example 6
Writing output to the harddrive
Serialize all data and metadata for selected variables and observations satisfying a given condition and write the output to disk
. jsonio out mpg foreign weight price make if rep78 == 1, w(all) filenm(test.json)
Example 7
Working with meta data
Serialize variable names to JSON object that is printed to the Stata console:
. jsonio out, metaprint(varnames)
[ "make", "price", "mpg", "rep78", "headroom", "trunk", "weight", "length", "turn", "displacement", "gear_ratio", "foreign" ]
Serialize variable labels to JSON object that is printed to the Stata console:
. jsonio out, metaprint(varlabels)
{
"mpg" : "Mileage (mpg)",
"price" : "Price",
"headroom" : "Headroom (in.)",
"rep78" : "Repair Record 1978",
"length" : "Length (in.)",
"weight" : "Weight (lbs.)",
"displacement" : "Displacement (cu. in.)",
"turn" : "Turn Circle (ft.) ",
"trunk" : "Trunk space (cu. ft.)",
"make" : "Make and Model",
"gear_ratio" : "Gear Ratio",
"foreign" : "Car type"
}