Currently, we only support the LAS 2.0 standard.
- Uses stdlib only, no third party libraries
- Easily unmarshal
lasdata intojson/yaml - Since .las files can be massive, we do not read the entire file into memory before lexing/parsing
- Data is read one rune at a time
- We fill a buffer, which is reset after each line, with necessary data as opposed to slicing into an existing string from memory
- Therefore, the "maximum" amount of data our lexer keeps in memory at any given time is a single line's worth
The following example uses this .las file as input
package main
import (
"os"
"github.com/openlas/golas"
)
func main() {
lasReader, _ := os.Open("samples/unwrapped.las")
las := golas.Parse(lasReader)
fmt.Printf("version : %s\n", las.Version())
fmt.Printf("wrap : %s\n\n", las.Wrap())
prettyPrintStructAsJSON(las)
}
func prettyPrintStructAsJSON(v interface{}) {
if j, e := json.MarshalIndent(v, "", " "); e != nil {
fmt.Printf("Error : %s \n", e.Error())
} else {
fmt.Printf("%s\n", string(j))
}
}Which gives us...
version : 2.0
wrap : NO
{
"Sections": [
{
"Name": "Version Information",
"Lines": [
{
"Mnem": "VERS",
"Units": "",
"Data": "2.0",
"Description": "CWLS LOG ASCII STANDARD -VERSION 2.0"
},
{
"Mnem": "WRAP",
"Units": "",
"Data": "NO",
"Description": "ONE LINE PER DEPTH STEP"
}
],
"Comments": null
},
{
"Name": "Well Information",
"Lines": [
{
"Mnem": "WELL",
"Units": "",
"Data": "NORVEHC MGSU 1 MITSUE 01-01",
"Description": "Well_name - WELL"
},
{
"Mnem": "LOC",
"Units": "",
"Data": "00/01-01-073-05W5/0",
"Description": "Location - LOCATION"
},
{
"Mnem": "UWI",
"Units": "",
"Data": "00/01-01-073-05W5/0",
"Description": "Uwi - UNIQUE WELL ID"
},
{
"Mnem": "ENTR",
"Units": "",
"Data": "JOHN",
"Description": "Entered - ENTERED BY"
},
{
"Mnem": "SRVC",
"Units": "",
"Data": "REGREBMULHCS",
"Description": "Scn - SERVICE COMPANY"
},
{
"Mnem": "DATE",
"Units": "",
"Data": "01 JAN 70",
"Description": "Date - LOG DATE"
},
{
"Mnem": "STRT",
"Units": "M",
"Data": "390",
"Description": "top_depth - START DEPTH"
},
{
"Mnem": "STOP",
"Units": "M",
"Data": "650",
"Description": "bot_depth - STOP DEPTH"
},
{
"Mnem": "STEP",
"Units": "M",
"Data": "0.25",
"Description": "increment - STEP LENGTH"
},
{
"Mnem": "NULL",
"Units": "",
"Data": "-999.2500",
"Description": "NULL Value"
}
],
"Comments": [
"#MNEM.UNIT DATA DESCRIPTION OF MNEMONIC",
"#--------- ------------------- -------------------------------",
"# Generated from Intellog Unique Number\tCW_0099_0099/WELL/0099"
]
},
{
"Name": "Curve Information",
"Lines": [
{
"Mnem": "DEPT",
"Units": "M",
"Data": "00 001 00 00",
"Description": "DEPTH - DEPTH"
},
{
"Mnem": "DPHI",
"Units": "V/V",
"Data": "00 890 00 00",
"Description": "PHID - DENSITY POROSITY (SANDSTONE)"
},
{
"Mnem": "NPHI",
"Units": "V/V",
"Data": "00 330 00 00",
"Description": "PHIN - NEUTRON POROSITY (SANDSTONE)"
},
{
"Mnem": "GR",
"Units": "API",
"Data": "00 310 00 00",
"Description": "GR - GAMMA RAY"
},
{
"Mnem": "CALI",
"Units": "MM",
"Data": "00 280 01 00",
"Description": "CAL - CALIPER"
},
{
"Mnem": "ILD",
"Units": "OHMM",
"Data": "00 120 00 00",
"Description": "RESD - DEEP RESISTIVITY (DIL)"
}
],
"Comments": [
"#MNEM.UNIT ERCB CURVE CODE CURVE DESCRIPTION",
"#----------- ------------------ ----------------------------------"
]
},
{
"Name": "Parameter Information",
"Lines": [
{
"Mnem": "GL",
"Units": "M",
"Data": "583.3",
"Description": "gl - GROUND LEVEL ELEVATION"
},
{
"Mnem": "EREF",
"Units": "M",
"Data": "589",
"Description": "kb - ELEVATION OF DEPTH REFERENCE"
},
{
"Mnem": "DATM",
"Units": "M",
"Data": "583.3",
"Description": "datum - DATUM ELEVATION"
},
{
"Mnem": "TDD",
"Units": "M",
"Data": "733.4",
"Description": "tdd - TOTAL DEPTH DRILLER"
},
{
"Mnem": "RUN",
"Units": "",
"Data": "ONE",
"Description": "Run - RUN NUMBER"
},
{
"Mnem": "ENG",
"Units": "",
"Data": "SIMMONS",
"Description": "Engineer - RECORDING ENGINEER"
},
{
"Mnem": "WIT",
"Units": "",
"Data": "SANK",
"Description": "Witness - WITNESSED BY"
},
{
"Mnem": "BASE",
"Units": "",
"Data": "S.L.",
"Description": "Branch - HOME BASE OF LOGGING UNIT"
},
{
"Mnem": "MUD",
"Units": "",
"Data": "GEL CHEM",
"Description": "Mud_type - MUD TYPE"
},
{
"Mnem": "MATR",
"Units": "",
"Data": "SANDSTONE",
"Description": "Logunit - NEUTRON MATRIX"
},
{
"Mnem": "TMAX",
"Units": "C",
"Data": "41",
"Description": "BHT - MAXIMUM RECORDED TEMPERATURE"
},
{
"Mnem": "BHTD",
"Units": "M",
"Data": "733.8",
"Description": "BHTDEP - MAXIMUM RECORDED TEMPERATURE"
},
{
"Mnem": "RMT",
"Units": "C",
"Data": "17",
"Description": "MDTP - TEMPERATURE OF MUD"
},
{
"Mnem": "MUDD",
"Units": "KG/M",
"Data": "1100",
"Description": "MWT - MUD DENSITY"
},
{
"Mnem": "NEUT",
"Units": "",
"Data": "1",
"Description": "NEUTRON - NEUTRON TYPE"
},
{
"Mnem": "RESI",
"Units": "",
"Data": "0",
"Description": "RESIST - RESISTIVITY TYPE"
},
{
"Mnem": "RM",
"Units": "OHMM",
"Data": "2.62",
"Description": "RM - RESISTIVITY OF MUD"
},
{
"Mnem": "RMC",
"Units": "OHMM",
"Data": "0",
"Description": "RMC - RESISTIVITY OF MUD CAKE"
},
{
"Mnem": "RMF",
"Units": "OHMM",
"Data": "1.02",
"Description": "RMF - RESISTIVITY OF MUD FILTRATE"
},
{
"Mnem": "SUFT",
"Units": "C",
"Data": "0",
"Description": "SUFT - SURFACE TEMPERATURE"
}
],
"Comments": [
"#MNEM.UNIT DATA DESCRIPTION OF MNEMONIC",
"#--------- ----------- ------------------------------"
]
},
{
"Name": "~My Custom Section",
"Lines": [
{
"Mnem": "MNEM_VAL",
"Units": "UNIT_VAL",
"Data": "DATA_VAL",
"Description": "DESCRIPTION_VAL"
}
],
"Comments": null
}
],
"Logs": [
[
"390.000",
"0.199",
"0.457",
"82.478",
"238.379",
"2.923"
],
[
"390.250",
"0.208",
"0.456",
"86.413",
"238.331",
"2.925"
],
[
"390.500",
"0.246",
"0.452",
"90.229",
"238.069",
"2.917"
],
[
"390.750",
"0.266",
"0.475",
"90.944",
"238.752",
"2.898"
],
[
"391.000",
"0.287",
"0.484",
"88.866",
"239.724",
"2.890"
],
[
"391.250",
"0.288",
"0.474",
"82.638",
"241.951",
"2.844"
],
[
"391.500",
"0.241",
"0.461",
"83.345",
"244.478",
"2.748"
],
[
"391.750",
"0.215",
"0.471",
"88.403",
"247.116",
"2.725"
],
[
"392.000",
"0.190",
"0.448",
"91.038",
"250.475",
"2.748"
]
]
}