Add floor, ceil and round functions. Closes #402

This commit is contained in:
Marko Mikulicic 2015-02-04 12:24:00 +01:00
parent 9e6b3bcefa
commit 8fdacbdf17
2 changed files with 176 additions and 1 deletions

View File

@ -44,7 +44,7 @@ func (function *Function) CheckArgTypes(args []Node) error {
function.name, len(function.argTypes), len(args),
)
}
if len(function.argTypes) - function.optionalArgs > len(args) {
if len(function.argTypes)-function.optionalArgs > len(args) {
return fmt.Errorf(
"too few arguments to function %v(): %v expected at least, %v given",
function.name, len(function.argTypes)-function.optionalArgs, len(args),
@ -291,6 +291,32 @@ func dropCommonLabelsImpl(timestamp clientmodel.Timestamp, args []Node) interfac
return vector
}
// === round(vector VectorNode) Vector ===
func roundImpl(timestamp clientmodel.Timestamp, args []Node) interface{} {
// round returns a number rounded to nearest integer.
// Ties are solved by rounding towards the even integer.
round := func(n float64) float64 {
if n-math.Floor(n) == 0.5 && int64(n)%2 == 0 {
n += math.Copysign(0.5, -n)
}
return math.Copysign(math.Floor(math.Abs(n)+0.5), n)
}
places := float64(0)
if len(args) >= 2 {
places = float64(args[1].(ScalarNode).Eval(timestamp))
}
pow := math.Pow(10, float64(places))
n := args[0].(VectorNode)
vector := n.Eval(timestamp)
for _, el := range vector {
el.Metric.Delete(clientmodel.MetricNameLabel)
el.Value = clientmodel.SampleValue(round(pow*float64(el.Value)) / pow)
}
return vector
}
// === scalar(node VectorNode) Scalar ===
func scalarImpl(timestamp clientmodel.Timestamp, args []Node) interface{} {
v := args[0].(VectorNode).Eval(timestamp)
@ -343,6 +369,17 @@ func countOverTimeImpl(timestamp clientmodel.Timestamp, args []Node) interface{}
})
}
// === floor(vector VectorNode) Vector ===
func floorImpl(timestamp clientmodel.Timestamp, args []Node) interface{} {
n := args[0].(VectorNode)
vector := n.Eval(timestamp)
for _, el := range vector {
el.Metric.Delete(clientmodel.MetricNameLabel)
el.Value = clientmodel.SampleValue(math.Floor(float64(el.Value)))
}
return vector
}
// === max_over_time(matrix MatrixNode) Vector ===
func maxOverTimeImpl(timestamp clientmodel.Timestamp, args []Node) interface{} {
return aggrOverTime(timestamp, args, func(values metric.Values) clientmodel.SampleValue {
@ -413,6 +450,17 @@ func absentImpl(timestamp clientmodel.Timestamp, args []Node) interface{} {
}
}
// === ceil(vector VectorNode) Vector ===
func ceilImpl(timestamp clientmodel.Timestamp, args []Node) interface{} {
n := args[0].(VectorNode)
vector := n.Eval(timestamp)
for _, el := range vector {
el.Metric.Delete(clientmodel.MetricNameLabel)
el.Value = clientmodel.SampleValue(math.Ceil(float64(el.Value)))
}
return vector
}
// === deriv(node MatrixNode) Vector ===
func derivImpl(timestamp clientmodel.Timestamp, args []Node) interface{} {
matrixNode := args[0].(MatrixNode)
@ -481,6 +529,12 @@ var functions = map[string]*Function{
returnType: VectorType,
callFn: bottomkImpl,
},
"ceil": {
name: "ceil",
argTypes: []ExprType{VectorType},
returnType: VectorType,
callFn: ceilImpl,
},
"count_over_time": {
name: "count_over_time",
argTypes: []ExprType{MatrixType},
@ -506,6 +560,12 @@ var functions = map[string]*Function{
returnType: VectorType,
callFn: dropCommonLabelsImpl,
},
"floor": {
name: "floor",
argTypes: []ExprType{VectorType},
returnType: VectorType,
callFn: floorImpl,
},
"max_over_time": {
name: "max_over_time",
argTypes: []ExprType{MatrixType},
@ -524,6 +584,13 @@ var functions = map[string]*Function{
returnType: VectorType,
callFn: rateImpl,
},
"round": {
name: "round",
argTypes: []ExprType{VectorType, ScalarType},
optionalArgs: 1,
returnType: VectorType,
callFn: roundImpl,
},
"scalar": {
name: "scalar",
argTypes: []ExprType{VectorType},

View File

@ -497,6 +497,114 @@ func TestExpressions(t *testing.T) {
fullRanges: 0,
intervalRanges: 2,
},
{
expr: `floor(0.004 * http_requests{group="production",job="api-server"})`,
output: []string{
`{group="production", instance="0", job="api-server"} => 0 @[%v]`,
`{group="production", instance="1", job="api-server"} => 0 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{
expr: `ceil(0.004 * http_requests{group="production",job="api-server"})`,
output: []string{
`{group="production", instance="0", job="api-server"} => 1 @[%v]`,
`{group="production", instance="1", job="api-server"} => 1 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{
expr: `round(0.004 * http_requests{group="production",job="api-server"})`,
output: []string{
`{group="production", instance="0", job="api-server"} => 0 @[%v]`,
`{group="production", instance="1", job="api-server"} => 1 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{ // Round should correctly handle negative numbers.
expr: `round(-1 * (0.004 * http_requests{group="production",job="api-server"}))`,
output: []string{
`{group="production", instance="0", job="api-server"} => -0 @[%v]`,
`{group="production", instance="1", job="api-server"} => -1 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{ // Round should round half to even.
expr: `round(0.005 * http_requests{group="production",job="api-server"})`,
output: []string{
`{group="production", instance="0", job="api-server"} => 0 @[%v]`,
`{group="production", instance="1", job="api-server"} => 1 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{
expr: `round(-1 * (0.005 * http_requests{group="production",job="api-server"}))`,
output: []string{
`{group="production", instance="0", job="api-server"} => 0 @[%v]`,
`{group="production", instance="1", job="api-server"} => -1 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{ // Round should round half to even.
expr: `round(1 + 0.005 * http_requests{group="production",job="api-server"})`,
output: []string{
`{group="production", instance="0", job="api-server"} => 2 @[%v]`,
`{group="production", instance="1", job="api-server"} => 2 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{
expr: `round(-1 * (1 + 0.005 * http_requests{group="production",job="api-server"}))`,
output: []string{
`{group="production", instance="0", job="api-server"} => -2 @[%v]`,
`{group="production", instance="1", job="api-server"} => -2 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{ // Round should accept a number of decimal places to round to.
expr: `round(0.0005 * http_requests{group="production",job="api-server"}, 1)`,
output: []string{
`{group="production", instance="0", job="api-server"} => 0 @[%v]`,
`{group="production", instance="1", job="api-server"} => 0.1 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{ // Round should look at last decimal place parity.
expr: `round(2.1 + 0.0005 * http_requests{group="production",job="api-server"}, 1)`,
output: []string{
`{group="production", instance="0", job="api-server"} => 2.2 @[%v]`,
`{group="production", instance="1", job="api-server"} => 2.2 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{
expr: `round(5.2 + 0.0005 * http_requests{group="production",job="api-server"}, 1)`,
output: []string{
`{group="production", instance="0", job="api-server"} => 5.2 @[%v]`,
`{group="production", instance="1", job="api-server"} => 5.3 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{ // Round should work correctly with negative numbers and multiple decimal places.
expr: `round(-1 * (5.2 + 0.0005 * http_requests{group="production",job="api-server"}), 1)`,
output: []string{
`{group="production", instance="0", job="api-server"} => -5.2 @[%v]`,
`{group="production", instance="1", job="api-server"} => -5.3 @[%v]`,
},
fullRanges: 0,
intervalRanges: 2,
},
{
expr: `avg_over_time(http_requests{group="production",job="api-server"}[1h])`,
output: []string{