Create JSON string from a Map with arrays as entries
0
My data structure object is a Map with the following structure:
"2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
I use JSON.stringify and then JSON.parse. However, I would need the elements to be somehow named so that I can reference them (e.g. when drawing a chart).
I tried the following but I get NaN as a value.
data = Object.keys(data).map(function (k)
return date: new Date(k), value: +data[k];
);
I would like to have something like this:
Key: "2018-09-25"
1:0
2:1
3:2
4:0
5:8
javascript collections
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
|
show 3 more comments
0
My data structure object is a Map with the following structure:
"2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
I use JSON.stringify and then JSON.parse. However, I would need the elements to be somehow named so that I can reference them (e.g. when drawing a chart).
I tried the following but I get NaN as a value.
data = Object.keys(data).map(function (k)
return date: new Date(k), value: +data[k];
);
I would like to have something like this:
Key: "2018-09-25"
1:0
2:1
3:2
4:0
5:8
javascript collections
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
3
It would help if you'd post the actual data structure in JavaScript terms, or at least a representative part of it. Also, it would be good to explain why you callJSON.stringify()and thenJSON.parse()on the data.
– Pointy
Nov 15 '18 at 17:24
Please also add the data structure you would like to transform your map to.
– Fabian Hinsenkamp
Nov 15 '18 at 17:29
Thanks for adding the desired result, but it's not clear what you want. Why not just post actual javascript?
– Mark Meyer
Nov 15 '18 at 17:34
2
Remove the "+" at "return date: new Date(k), value: +data[k];". The correct line is "return date: new Date(k), value: data[k];"
– TwilightTitus
Nov 15 '18 at 17:35
@MarkMeyer Basically I want to draw a chart. But I do not know how to reference individual elements in the arrays. The chart should have 5 lines, for each element.
– John V
Nov 15 '18 at 17:36
|
show 3 more comments
0
0
0
My data structure object is a Map with the following structure:
"2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
I use JSON.stringify and then JSON.parse. However, I would need the elements to be somehow named so that I can reference them (e.g. when drawing a chart).
I tried the following but I get NaN as a value.
data = Object.keys(data).map(function (k)
return date: new Date(k), value: +data[k];
);
I would like to have something like this:
Key: "2018-09-25"
1:0
2:1
3:2
4:0
5:8
javascript collections
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
My data structure object is a Map with the following structure:
"2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
I use JSON.stringify and then JSON.parse. However, I would need the elements to be somehow named so that I can reference them (e.g. when drawing a chart).
I tried the following but I get NaN as a value.
data = Object.keys(data).map(function (k)
return date: new Date(k), value: +data[k];
);
I would like to have something like this:
Key: "2018-09-25"
1:0
2:1
3:2
4:0
5:8
javascript collections
javascript collections
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
edited Nov 15 '18 at 17:35
ponury-kostek
4,77841224
4,77841224
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
asked Nov 15 '18 at 17:23
John VJohn V
2,02482546
2,02482546
3
It would help if you'd post the actual data structure in JavaScript terms, or at least a representative part of it. Also, it would be good to explain why you callJSON.stringify()and thenJSON.parse()on the data.
– Pointy
Nov 15 '18 at 17:24
Please also add the data structure you would like to transform your map to.
– Fabian Hinsenkamp
Nov 15 '18 at 17:29
Thanks for adding the desired result, but it's not clear what you want. Why not just post actual javascript?
– Mark Meyer
Nov 15 '18 at 17:34
2
Remove the "+" at "return date: new Date(k), value: +data[k];". The correct line is "return date: new Date(k), value: data[k];"
– TwilightTitus
Nov 15 '18 at 17:35
@MarkMeyer Basically I want to draw a chart. But I do not know how to reference individual elements in the arrays. The chart should have 5 lines, for each element.
– John V
Nov 15 '18 at 17:36
|
show 3 more comments
3
It would help if you'd post the actual data structure in JavaScript terms, or at least a representative part of it. Also, it would be good to explain why you callJSON.stringify()and thenJSON.parse()on the data.
– Pointy
Nov 15 '18 at 17:24
Please also add the data structure you would like to transform your map to.
– Fabian Hinsenkamp
Nov 15 '18 at 17:29
Thanks for adding the desired result, but it's not clear what you want. Why not just post actual javascript?
– Mark Meyer
Nov 15 '18 at 17:34
2
Remove the "+" at "return date: new Date(k), value: +data[k];". The correct line is "return date: new Date(k), value: data[k];"
– TwilightTitus
Nov 15 '18 at 17:35
@MarkMeyer Basically I want to draw a chart. But I do not know how to reference individual elements in the arrays. The chart should have 5 lines, for each element.
– John V
Nov 15 '18 at 17:36
3
3
It would help if you'd post the actual data structure in JavaScript terms, or at least a representative part of it. Also, it would be good to explain why you call
JSON.stringify() and then JSON.parse() on the data.– Pointy
Nov 15 '18 at 17:24
It would help if you'd post the actual data structure in JavaScript terms, or at least a representative part of it. Also, it would be good to explain why you call
JSON.stringify() and then JSON.parse() on the data.– Pointy
Nov 15 '18 at 17:24
Please also add the data structure you would like to transform your map to.
– Fabian Hinsenkamp
Nov 15 '18 at 17:29
Please also add the data structure you would like to transform your map to.
– Fabian Hinsenkamp
Nov 15 '18 at 17:29
Thanks for adding the desired result, but it's not clear what you want. Why not just post actual javascript?
– Mark Meyer
Nov 15 '18 at 17:34
Thanks for adding the desired result, but it's not clear what you want. Why not just post actual javascript?
– Mark Meyer
Nov 15 '18 at 17:34
2
2
Remove the "+" at "return date: new Date(k), value: +data[k];". The correct line is "return date: new Date(k), value: data[k];"
– TwilightTitus
Nov 15 '18 at 17:35
Remove the "+" at "return date: new Date(k), value: +data[k];". The correct line is "return date: new Date(k), value: data[k];"
– TwilightTitus
Nov 15 '18 at 17:35
@MarkMeyer Basically I want to draw a chart. But I do not know how to reference individual elements in the arrays. The chart should have 5 lines, for each element.
– John V
Nov 15 '18 at 17:36
@MarkMeyer Basically I want to draw a chart. But I do not know how to reference individual elements in the arrays. The chart should have 5 lines, for each element.
– John V
Nov 15 '18 at 17:36
|
show 3 more comments
1 Answer
1
active
oldest
votes
0
Since you are using map() it looks like you want an array as a final result. But, since the array will be a different size, map() doesn't really work. You can use reduce to flatten out the inner arrays into one big array:
let o = "2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
let newAr = Object.entries(o).reduce((arr, [key, values]) =>
return arr.concat(values.map(n => (date: new Date(key), value: n)))
, )
console.log(newAr)Is that what you're after?
answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
1
Thanks, yes! It provides the format I was trying to get.
– John V
Nov 15 '18 at 17:41
May I ask, how do I get the length of the array? I tried something like newAr.Value.length but that does not work.
– John V
Nov 15 '18 at 17:57
The length of the final array is justnewAr.length, is that what you mean?
– Mark Meyer
Nov 15 '18 at 18:00
No, I mean I should get 5 - there are 5 elements in an array under each key.
– John V
Nov 15 '18 at 18:02
Now that it's flattened out, it's a little work to get the length. The easiest way is to just look at your original object and get the length of the array. In the example above: ` o['2018-09-25'].length`. Otherwise you'll need to filter or reduce the result to regroup the items.
– Mark Meyer
Nov 15 '18 at 18:04
add a comment |
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1 Answer
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votes
0
Since you are using map() it looks like you want an array as a final result. But, since the array will be a different size, map() doesn't really work. You can use reduce to flatten out the inner arrays into one big array:
let o = "2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
let newAr = Object.entries(o).reduce((arr, [key, values]) =>
return arr.concat(values.map(n => (date: new Date(key), value: n)))
, )
console.log(newAr)Is that what you're after?
answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
1
Thanks, yes! It provides the format I was trying to get.
– John V
Nov 15 '18 at 17:41
May I ask, how do I get the length of the array? I tried something like newAr.Value.length but that does not work.
– John V
Nov 15 '18 at 17:57
The length of the final array is justnewAr.length, is that what you mean?
– Mark Meyer
Nov 15 '18 at 18:00
No, I mean I should get 5 - there are 5 elements in an array under each key.
– John V
Nov 15 '18 at 18:02
Now that it's flattened out, it's a little work to get the length. The easiest way is to just look at your original object and get the length of the array. In the example above: ` o['2018-09-25'].length`. Otherwise you'll need to filter or reduce the result to regroup the items.
– Mark Meyer
Nov 15 '18 at 18:04
add a comment |
0
Since you are using map() it looks like you want an array as a final result. But, since the array will be a different size, map() doesn't really work. You can use reduce to flatten out the inner arrays into one big array:
let o = "2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
let newAr = Object.entries(o).reduce((arr, [key, values]) =>
return arr.concat(values.map(n => (date: new Date(key), value: n)))
, )
console.log(newAr)Is that what you're after?
answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
1
Thanks, yes! It provides the format I was trying to get.
– John V
Nov 15 '18 at 17:41
May I ask, how do I get the length of the array? I tried something like newAr.Value.length but that does not work.
– John V
Nov 15 '18 at 17:57
The length of the final array is justnewAr.length, is that what you mean?
– Mark Meyer
Nov 15 '18 at 18:00
No, I mean I should get 5 - there are 5 elements in an array under each key.
– John V
Nov 15 '18 at 18:02
Now that it's flattened out, it's a little work to get the length. The easiest way is to just look at your original object and get the length of the array. In the example above: ` o['2018-09-25'].length`. Otherwise you'll need to filter or reduce the result to regroup the items.
– Mark Meyer
Nov 15 '18 at 18:04
add a comment |
0
0
0
Since you are using map() it looks like you want an array as a final result. But, since the array will be a different size, map() doesn't really work. You can use reduce to flatten out the inner arrays into one big array:
let o = "2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
let newAr = Object.entries(o).reduce((arr, [key, values]) =>
return arr.concat(values.map(n => (date: new Date(key), value: n)))
, )
console.log(newAr)Is that what you're after?
answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
Since you are using map() it looks like you want an array as a final result. But, since the array will be a different size, map() doesn't really work. You can use reduce to flatten out the inner arrays into one big array:
let o = "2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
let newAr = Object.entries(o).reduce((arr, [key, values]) =>
return arr.concat(values.map(n => (date: new Date(key), value: n)))
, )
console.log(newAr)Is that what you're after?
let o = "2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
let newAr = Object.entries(o).reduce((arr, [key, values]) =>
return arr.concat(values.map(n => (date: new Date(key), value: n)))
, )
console.log(newAr)let o = "2018-09-25":[0,1,2,0,8],
"2018-10-17":[0,2,0,0,0],
"2018-10-26":[0,2,1,0,0],
"2018-10-29":[0,2,2,1,0],
"2018-10-31":[0,3,2,1,0],
"2018-11-01":[0,3,3,1,0],
"2018-11-02":[0,4,4,1,0]
let newAr = Object.entries(o).reduce((arr, [key, values]) =>
return arr.concat(values.map(n => (date: new Date(key), value: n)))
, )
console.log(newAr)answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
answered Nov 15 '18 at 17:40
Mark MeyerMark Meyer
39.5k33162
39.5k33162
1
Thanks, yes! It provides the format I was trying to get.
– John V
Nov 15 '18 at 17:41
May I ask, how do I get the length of the array? I tried something like newAr.Value.length but that does not work.
– John V
Nov 15 '18 at 17:57
The length of the final array is justnewAr.length, is that what you mean?
– Mark Meyer
Nov 15 '18 at 18:00
No, I mean I should get 5 - there are 5 elements in an array under each key.
– John V
Nov 15 '18 at 18:02
Now that it's flattened out, it's a little work to get the length. The easiest way is to just look at your original object and get the length of the array. In the example above: ` o['2018-09-25'].length`. Otherwise you'll need to filter or reduce the result to regroup the items.
– Mark Meyer
Nov 15 '18 at 18:04
add a comment |
1
Thanks, yes! It provides the format I was trying to get.
– John V
Nov 15 '18 at 17:41
May I ask, how do I get the length of the array? I tried something like newAr.Value.length but that does not work.
– John V
Nov 15 '18 at 17:57
The length of the final array is justnewAr.length, is that what you mean?
– Mark Meyer
Nov 15 '18 at 18:00
No, I mean I should get 5 - there are 5 elements in an array under each key.
– John V
Nov 15 '18 at 18:02
Now that it's flattened out, it's a little work to get the length. The easiest way is to just look at your original object and get the length of the array. In the example above: ` o['2018-09-25'].length`. Otherwise you'll need to filter or reduce the result to regroup the items.
– Mark Meyer
Nov 15 '18 at 18:04
1
1
Thanks, yes! It provides the format I was trying to get.
– John V
Nov 15 '18 at 17:41
Thanks, yes! It provides the format I was trying to get.
– John V
Nov 15 '18 at 17:41
May I ask, how do I get the length of the array? I tried something like newAr.Value.length but that does not work.
– John V
Nov 15 '18 at 17:57
May I ask, how do I get the length of the array? I tried something like newAr.Value.length but that does not work.
– John V
Nov 15 '18 at 17:57
The length of the final array is just
newAr.length, is that what you mean?– Mark Meyer
Nov 15 '18 at 18:00
The length of the final array is just
newAr.length, is that what you mean?– Mark Meyer
Nov 15 '18 at 18:00
No, I mean I should get 5 - there are 5 elements in an array under each key.
– John V
Nov 15 '18 at 18:02
No, I mean I should get 5 - there are 5 elements in an array under each key.
– John V
Nov 15 '18 at 18:02
Now that it's flattened out, it's a little work to get the length. The easiest way is to just look at your original object and get the length of the array. In the example above: ` o['2018-09-25'].length`. Otherwise you'll need to filter or reduce the result to regroup the items.
– Mark Meyer
Nov 15 '18 at 18:04
Now that it's flattened out, it's a little work to get the length. The easiest way is to just look at your original object and get the length of the array. In the example above: ` o['2018-09-25'].length`. Otherwise you'll need to filter or reduce the result to regroup the items.
– Mark Meyer
Nov 15 '18 at 18:04
add a comment |
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3
It would help if you'd post the actual data structure in JavaScript terms, or at least a representative part of it. Also, it would be good to explain why you call
JSON.stringify()and thenJSON.parse()on the data.– Pointy
Nov 15 '18 at 17:24
Please also add the data structure you would like to transform your map to.
– Fabian Hinsenkamp
Nov 15 '18 at 17:29
Thanks for adding the desired result, but it's not clear what you want. Why not just post actual javascript?
– Mark Meyer
Nov 15 '18 at 17:34
2
Remove the "+" at "return date: new Date(k), value: +data[k];". The correct line is "return date: new Date(k), value: data[k];"
– TwilightTitus
Nov 15 '18 at 17:35
@MarkMeyer Basically I want to draw a chart. But I do not know how to reference individual elements in the arrays. The chart should have 5 lines, for each element.
– John V
Nov 15 '18 at 17:36