Sum and Avg in Map Reduce
Let me start with the data sample:
{
"_id": {
"$oid": "5be18d5cedc30c3a396e3646"
},
"sex": "Male",
"first_name": "Anthony",
"last_name": "Nichols",
"job": "Internal Auditor",
"height": "162.68",
"weight": "68.37",
"birth_date": "2013-05-23T16:10:58Z",
"nationality": "Indonesia"
}
I'm trying to return avg height of female and male and this is how my map - reduce looks like:
var mapFunction1 = function() {
emit(this.sex, this.height);
};
var reduceFunction1 = function(keySex,valuesHeight) {
return Array.avg(valuesHeight);
};
db.people.mapReduce(
mapFunction1,
reduceFunction1,
{out:"example"}
)
And as a result i get
{ "_id" : "Female", "value" : NaN }
{ "_id" : "Male", "value" : NaN }
For example, when I try to sum height instead of making avg it just print out the height of every female and male. What am I doing wrong? Can u guys please help me.
mapreduce
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
add a comment |
Let me start with the data sample:
{
"_id": {
"$oid": "5be18d5cedc30c3a396e3646"
},
"sex": "Male",
"first_name": "Anthony",
"last_name": "Nichols",
"job": "Internal Auditor",
"height": "162.68",
"weight": "68.37",
"birth_date": "2013-05-23T16:10:58Z",
"nationality": "Indonesia"
}
I'm trying to return avg height of female and male and this is how my map - reduce looks like:
var mapFunction1 = function() {
emit(this.sex, this.height);
};
var reduceFunction1 = function(keySex,valuesHeight) {
return Array.avg(valuesHeight);
};
db.people.mapReduce(
mapFunction1,
reduceFunction1,
{out:"example"}
)
And as a result i get
{ "_id" : "Female", "value" : NaN }
{ "_id" : "Male", "value" : NaN }
For example, when I try to sum height instead of making avg it just print out the height of every female and male. What am I doing wrong? Can u guys please help me.
mapreduce
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
add a comment |
Let me start with the data sample:
{
"_id": {
"$oid": "5be18d5cedc30c3a396e3646"
},
"sex": "Male",
"first_name": "Anthony",
"last_name": "Nichols",
"job": "Internal Auditor",
"height": "162.68",
"weight": "68.37",
"birth_date": "2013-05-23T16:10:58Z",
"nationality": "Indonesia"
}
I'm trying to return avg height of female and male and this is how my map - reduce looks like:
var mapFunction1 = function() {
emit(this.sex, this.height);
};
var reduceFunction1 = function(keySex,valuesHeight) {
return Array.avg(valuesHeight);
};
db.people.mapReduce(
mapFunction1,
reduceFunction1,
{out:"example"}
)
And as a result i get
{ "_id" : "Female", "value" : NaN }
{ "_id" : "Male", "value" : NaN }
For example, when I try to sum height instead of making avg it just print out the height of every female and male. What am I doing wrong? Can u guys please help me.
mapreduce
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
Let me start with the data sample:
{
"_id": {
"$oid": "5be18d5cedc30c3a396e3646"
},
"sex": "Male",
"first_name": "Anthony",
"last_name": "Nichols",
"job": "Internal Auditor",
"height": "162.68",
"weight": "68.37",
"birth_date": "2013-05-23T16:10:58Z",
"nationality": "Indonesia"
}
I'm trying to return avg height of female and male and this is how my map - reduce looks like:
var mapFunction1 = function() {
emit(this.sex, this.height);
};
var reduceFunction1 = function(keySex,valuesHeight) {
return Array.avg(valuesHeight);
};
db.people.mapReduce(
mapFunction1,
reduceFunction1,
{out:"example"}
)
And as a result i get
{ "_id" : "Female", "value" : NaN }
{ "_id" : "Male", "value" : NaN }
For example, when I try to sum height instead of making avg it just print out the height of every female and male. What am I doing wrong? Can u guys please help me.
mapreduce
mapreduce
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
asked Nov 13 '18 at 17:28
Bartek WiszenkoBartek Wiszenko
12
12
add a comment |
add a comment |
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