有人可以帮助我解释为什么写入相同的数据没有正确转换为我需要的符号。
我似乎无法找出为什么我的对象无法正确转换为正确转换的示例。
var data2_JSON = document.getElementById('JSON2').value;
var obj2 = JSON.parse(data2_JSON);
function getMaxY() {
var max = 0;
//!! only every other item in array is having sumps2
for(var i = 1; i < obj2.dataset2.length; i+=2) {
if(Number(obj2.dataset2[i].p1) > max) {
max = Number(obj2.dataset2[i].p1);
}
}
return Number(max|0); // convert to integer number
}
var sNum = "1.23e-2";
alert(parseFloat(sNum));
alert(parseFloat(obj2.dataset2[4].p1)); <textarea id="JSON2">
{
"dataset2": [ {"p1" : "2.097E-15 "} ,{"sumps2" :" 12"},
{"p1" : "3.6039E-13 "} ,{"sumps2" :" 5"},
{"p1" : "5.6446E-16 "} ,{"sumps2" :" 14"},
{"p1" : "-4.9850E-20 "} ,{"sumps2" :" 7"},
{"p1" : "-3.430E-21 "} ,{"sumps2" :" 6"},
{"p1" : "9.8509E-20 "} ,{"sumps2" :" 7"},
{"p1" : "6.4500E-20 "} ,{"sumps2" :" 4"},
{"p1" : "-4.2150E-20 "} ,{"sumps2" :" 17"},
{"p1" : "-1.835E-21 "} ,{"sumps2" :" 11"},
{"p1" : "-4.5872E-20 "} ,{"sumps2" :" 13"},
{"p1" : "-9.7921E-21 "} ,{"sumps2" :" 9"},
{"p1" : "-1.2206E-19 "} ,{"sumps2" :" 4"},
{"p1" : "-3.843E-20 "} ,{"sumps2" :" 3"},
{"p1" : "-2.1871E-20 "} ,{"sumps2" :" 10"},
{"p1" : "3.0353E-20 "} ,{"sumps2" :" 7"},
{"p1" : "3.4013E-20 "} ,{"sumps2" :" 17"},
{"p1" : "-1.20536E-19 "} ,{"sumps2" :" 17"},
{"p1" : "2.9374E-19 "} ,{"sumps2" :" 12"},
{"p1" : "9.5229E-20 "} ,{"sumps2" :" 16"},
{"p1" : "0.15006E-15 "} ,{"sumps2" :" 6"},
{"p1" : "1.01736E-20 "} ,{"sumps2" :" 10"},
{"p1" : "4.966E-21 "} ,{"sumps2" :" 1"},
{"p1" : "4.08210E-16 "} ,{"sumps2" :" 7"},
{"p1" : "2.878973E-15 "} ,{"sumps2" :" 12"},
{"p1" : "2.49E-15 "} ,{"sumps2" :" 3"},
{"p1" : "4.4632E-15 "} ,{"sumps2" :" 9"},
{"p1" : "2.35454E-15 "} ,{"sumps2" :" 6"},
{"p1" : "7E-18 "} ,{"sumps2" :" 2"},
{"p1" : "9.53764E-15 "} ,{"sumps2" :" 4"},
{"p1" : "3.32849E-15 "} ,{"sumps2" :" 7"},
{"p1" : "1.0E-16 "} ,{"sumps2" :" 8"},
{"p1" : "1.88E-11 "} ,{"sumps2" :" 8"},
{"p1" : "5.16E-21 "} ,{"sumps2" :" 3"},
{"p1" : "5.95492E-15 "} ,{"sumps2" :" 9"},
{"p1" : "4.2792E-16 "} ,{"sumps2" :" 5"},
{"p1" : "7.704E-17 "} ,{"sumps2" :" 12"},
{"p1" : "1.3051E-14 "} ,{"sumps2" :" 3"},
{"p1" : "4.809E-17 "} ,{"sumps2" :" 4"},
{"p1" : "7.092E-15 "} ,{"sumps2" :" 4"},
{"p1" : "4.8590E-15 "} ,{"sumps2" :" 15"},
{"p1" : "5.849955E-15 "} ,{"sumps2" :" 17"},
{"p1" : "1.7614E-15 "} ,{"sumps2" :" 7"},
{"p1" : "1.200E-16 "} ,{"sumps2" :" 2"},
{"p1" : "7.83718E-17 "} ,{"sumps2" :" 10"},
{"p1" : "0.01223E-15 "} ,{"sumps2" :" 3"},
{"p1" : "1.071167E-14 "} ,{"sumps2" :" 12"},
{"p1" : "3.91070E-16 "} ,{"sumps2" :" 14"},
{"p1" : "1.99E-12 "} ,{"sumps2" :" 5"},
{"p1" : "2.56763E-16 "} ,{"sumps2" :" 8"},
{"p1" : "4.4259E-16 "} ,{"sumps2" :" 5"},
{"p1" : "1.700E-15 "} ,{"sumps2" :" 4"},
{"p1" : "1.299202E-15 "} ,{"sumps2" :" 6"},
{"p1" : "1.516E-16 "} ,{"sumps2" :" 10"},
{"p1" : "1.889254E-13 "} ,{"sumps2" :" 5"},
{"p1" : "1.93754256E-13 "} ,{"sumps2" :" 4"},
{"p1" : "1.1994E-15 "} ,{"sumps2" :" 5"},
{"p1" : "2.9E-16 "} ,{"sumps2" :" 2"},
{"p1" : "6.6E-15 "} ,{"sumps2" :" 3"},
{"p1" : "2.99E-19 "} ,{"sumps2" :" 10"},
{"p1" : "6.6212E-16 "} ,{"sumps2" :" 3"},
{"p1" : "7.7389E-20 "} ,{"sumps2" :" 17"},
{"p1" : "3.10998E-15 "} ,{"sumps2" :" 7"},
{"p1" : "5.509E-14 "} ,{"sumps2" :" 5"},
{"p1" : "3.06E-17 "} ,{"sumps2" :" 3"},
{"p1" : "1.295235E-15 "} ,{"sumps2" :" 20"},
{"p1" : "6.3562E-16 "} ,{"sumps2" :" 7"},
{"p1" : "0.381E-15 "} ,{"sumps2" :" 3"},
{"p1" : "0.21525E-15 "} ,{"sumps2" :" 6"},
{"p1" : "2.048265E-15 "} ,{"sumps2" :" 8"},
{"p1" : "7.3505E-18 "} ,{"sumps2" :" 10"},
{"p1" : "1.7666E-20 "} ,{"sumps2" :" 9"},
{"p1" : "0.057E-15 "} ,{"sumps2" :" 9"},
{"p1" : "1.342243E-14 "} ,{"sumps2" :" 15"},
{"p1" : "2.4075E-19 "} ,{"sumps2" :" 5"},
{"p1" : "1.3037E-14 "} ,{"sumps2" :" 20"},
{"p1" : "4.76594E-16 "} ,{"sumps2" :" 3"},
{"p1" : "4.396862E-15 "} ,{"sumps2" :" 13"},
{"p1" : "1.5382E-15 "} ,{"sumps2" :" 12"},
{"p1" : "5.57316E-15 "} ,{"sumps2" :" 3"},
{"p1" : "7.9E-20 "} ,{"sumps2" :" 3"},
{"p1" : "7.6601E-17 "} ,{"sumps2" :" 3"},
{"p1" : "0E-15 "} ,{"sumps2" :" 6"},
{"p1" : "2.759E-14 "} ,{"sumps2" :" 10"},
{"p1" : "1.16338E-15 "} ,{"sumps2" :" 15"},
{"p1" : "39.3444E-15 "} ,{"sumps2" :" 2"},
{"p1" : "5.729370E-20 "} ,{"sumps2" :" 9"},
{"p1" : "1.48347E-16 "} ,{"sumps2" :" 19"},
{"p1" : "3.371E-15 "} ,{"sumps2" :" 4"},
{"p1" : "1.02649E-16 "} ,{"sumps2" :" 6"},
{"p1" : "0E-15 "} ,{"sumps2" :" 2"},
{"p1" : "5.753107E-15 "} ,{"sumps2" :" 16"},
{"p1" : "2.37227E-15 "} ,{"sumps2" :" 7"},
{"p1" : "1.02119E-14 "} ,{"sumps2" :" 15"},
{"p1" : "36.70E-15 "} ,{"sumps2" :" 3"},
{"p1" : "0.21E-15 "} ,{"sumps2" :" 3"},
{"p1" : "5.3E-16 "} ,{"sumps2" :" 15"},
{"p1" : "1.39825E-15 "} ,{"sumps2" :" 6"},
{"p1" : "5.82E-12 "} ,{"sumps2" :" 3"},
{"p1" : "5.582339E-15 "} ,{"sumps2" :" 17"},
{"p1" : "2.3090E-14 "} ,{"sumps2" :" 6"},
{"p1" : "0.206E-15 "} ,{"sumps2" :" 4"},
{"p1" : "1.17E-21 "} ,{"sumps2" :" 13"},
{"p1" : "0.6968E-15 "} ,{"sumps2" :" 5"},
{"p1" : "3.0092E-17 "} ,{"sumps2" :" 9"},
{"p1" : "17.727E-15 "} ,{"sumps2" :" 14"},
{"p1" : "7.36052E-17 "} ,{"sumps2" :" 6"},
{"p1" : "6.5E-11 "} ,{"sumps2" :" 5"},
{"p1" : "4.00530E-14 "} ,{"sumps2" :" 15"},
{"p1" : "1.5509E-14 "} ,{"sumps2" :" 6"},
{"p1" : "5.354E-15 "} ,{"sumps2" :" 13"},
{"p1" : "1.60E-16 "} ,{"sumps2" :" 1"},
{"p1" : "4.22765E-13 "} ,{"sumps2" :" 4"},
{"p1" : "425.05E-15 "} ,{"sumps2" :" 6"},
{"p1" : "11.5E-15 "} ,{"sumps2" :" 3"},
{"p1" : "5.65E-16 "} ,{"sumps2" :" 3"},
{"p1" : "5.1784338E-14 "} ,{"sumps2" :" 11"},
{"p1" : "3.6694515E-15 "} ,{"sumps2" :" 13"},
{"p1" : "0.44811E-15 "} ,{"sumps2" :" 2"},
{"p1" : "4.78924621E-13 "} ,{"sumps2" :" 3"},
{"p1" : "8.2E-16 "} ,{"sumps2" :" 8"},
{"p1" : "1.5422691E-14 "} ,{"sumps2" :" 19"},
{"p1" : "3.94E-15 "} ,{"sumps2" :" 3"},
{"p1" : "7.65E-15 "} ,{"sumps2" :" 3"},
{"p1" : "1.426028E-13 "} ,{"sumps2" :" 11"},
{"p1" : "5.96E-15 "} ,{"sumps2" :" 3"},
{"p1" : "2.78E-15 "} ,{"sumps2" :" 9"},
{"p1" : "1.302098E-15 "} ,{"sumps2" :" 5"},
{"p1" : "0.000235E-15 "} ,{"sumps2" :" 2"},
{"p1" : "0.00001235E-15 "} ,{"sumps2" :" 6"},
{"p1" : "5.94681E-17 "} ,{"sumps2" :" 18"},
{"p1" : "9.5913E-21 "} ,{"sumps2" :" 8"},
{"p1" : "5.94494E-14 "} ,{"sumps2" :" 12"},
{"p1" : "1.75E-20 "} ,{"sumps2" :" 7"},
{"p1" : "0.00724E-15 "} ,{"sumps2" :" 6"},
{"p1" : "4.732E-20 "} ,{"sumps2" :" 2"},
{"p1" : "2.54237E-14 "} ,{"sumps2" :" 5"},
{"p1" : "0.08837E-15 "} ,{"sumps2" :" 3"},
{"p1" : "8.30442E-16 "} ,{"sumps2" :" 12"},
{"p1" : "1.698E-15 "} ,{"sumps2" :" 3"},
{"p1" : "29.8087E-15 "} ,{"sumps2" :" 18"},
{"p1" : "0.5479E-15 "} ,{"sumps2" :" 2"},
{"p1" : "1.99573E-15 "} ,{"sumps2" :" 3"},
{"p1" : "3.7481E-15 "} ,{"sumps2" :" 19"},
{"p1" : "7.1229E-15 "} ,{"sumps2" :" 3"},
{"p1" : "1.046741E-13 "} ,{"sumps2" :" 17"},
{"p1" : "7.9592E-14 "} ,{"sumps2" :" 3"},
{"p1" : "1.097087E-14 "} ,{"sumps2" :" 5"},
{"p1" : "3.82E-15 "} ,{"sumps2" :" 8"},
{"p1" : "3.1722E-15 "} ,{"sumps2" :" 20"},
{"p1" : "3.38E-21 "} ,{"sumps2" :" 3"},
{"p1" : "4.923E-21 "} ,{"sumps2" :" 8"},
{"p1" : "0.7357E-15 "} ,{"sumps2" :" 3"},
{"p1" : "6.421E-15 "} ,{"sumps2" :" 8"},
{"p1" : "0.1525E-15 "} ,{"sumps2" :" 12"},
{"p1" : "3.798787E-15 "} ,{"sumps2" :" 15"},
{"p1" : "0.0267E-15 "} ,{"sumps2" :" 17"},
{"p1" : "0.03191E-15 "} ,{"sumps2" :" 9"},
{"p1" : "9.15201E-15 "} ,{"sumps2" :" 13"},
{"p1" : "5.500309E-14 "} ,{"sumps2" :" 3"},
{"p1" : "6.853E-19 "} ,{"sumps2" :" 12"},
{"p1" : "0.1260E-15 "} ,{"sumps2" :" 2"},
{"p1" : "4E-16 "} ,{"sumps2" :" 1"},
{"p1" : "1.49067E-20 "} ,{"sumps2" :" 5"},
{"p1" : "7.2819E-15 "} ,{"sumps2" :" 7"},
{"p1" : "6.983E-14 "} ,{"sumps2" :" 22"},
{"p1" : "4.4E-20 "} ,{"sumps2" :" 4"},
{"p1" : "9.2640E-17 "} ,{"sumps2" :" 11"},
{"p1" : "293.11E-15 "} ,{"sumps2" :" 4"},
{"p1" : "1.132879E-13 "} ,{"sumps2" :" 4"},
{"p1" : "1.895713E-14 "} ,{"sumps2" :" 19"},
{"p1" : "5.704E-15 "} ,{"sumps2" :" 10"},
{"p1" : "1.22e-14 "} ,{"sumps2" :" 0"},
{"p1" : "5.46883E-15 "} ,{"sumps2" :" 11"},
{"p1" : "1.75993E-18 "} ,{"sumps2" :" 6"},
{"p1" : "8.92E-16 "} ,{"sumps2" :" 8"},
{"p1" : "1.6161E-15 "} ,{"sumps2" :" 9"},
{"p1" : "1.682112E-14 "} ,{"sumps2" :" 14"},
{"p1" : "2.73E-15 "} ,{"sumps2" :" 3"},
{"p1" : "16.660E-15 "} ,{"sumps2" :" 5"},
{"p1" : "9.770E-16 "} ,{"sumps2" :" 4"},
{"p1" : "7.7860E-21 "} ,{"sumps2" :" 5"},
{"p1" : "1.079865E-15 "} ,{"sumps2" :" 17"},
{"p1" : "1.618890E-15 "} ,{"sumps2" :" 14"},
{"p1" : "4.21E-15 "} ,{"sumps2" :" 3"},
{"p1" : "5.6E-14 "} ,{"sumps2" :" 30"},
{"p1" : "0.378E-15 "} ,{"sumps2" :" 1"},
{"p1" : "0.401E-15 "} ,{"sumps2" :" 3"},
{"p1" : "3.0825E-15 "} ,{"sumps2" :" 4"},
{"p1" : "0.0449E-15 "} ,{"sumps2" :" 12"},
{"p1" : "1.68114E-16 "} ,{"sumps2" :" 14"},
{"p1" : "0.139E-15 "} ,{"sumps2" :" 6"},
{"p1" : "0.58E-15 "} ,{"sumps2" :" 24"},
{"p1" : "0.7534E-15 "} ,{"sumps2" :" 5"},
{"p1" : "2.105178E-15 "} ,{"sumps2" :" 7"},
{"p1" : "2.44174E-15 "} ,{"sumps2" :" 11"},
{"p1" : "12.169E-15 "} ,{"sumps2" :" 4"},
{"p1" : "1.89E-17 "} ,{"sumps2" :" 13"},
{"p1" : "3.47811E-15 "} ,{"sumps2" :" 7"},
{"p1" : "9.3E-18 "} ,{"sumps2" :" 4"},
{"p1" : "1.04550E-16 "} ,{"sumps2" :" 6"},
{"p1" : "1.70932E-15 "} ,{"sumps2" :" 9"},
{"p1" : "9.963E-16 "} ,{"sumps2" :" 5"},
{"p1" : "1.279E-15 "} ,{"sumps2" :" 6"},
{"p1" : "4.437E-15 "} ,{"sumps2" :" 8"},
{"p1" : "9.778E-15 "} ,{"sumps2" :" 9"},
{"p1" : "1.25008E-13 "} ,{"sumps2" :" 16"},
{"p1" : "6.799219E-15 "} ,{"sumps2" :" 5"},
{"p1" : "3.5393E-15 "} ,{"sumps2" :" 12"},
{"p1" : "0.0390E-15 "} ,{"sumps2" :" 3"},
{"p1" : "8.1E-16 "} ,{"sumps2" :" 32"},
{"p1" : "1.644E-15 "} ,{"sumps2" :" 1"},
{"p1" : "9.497E-15 "} ,{"sumps2" :" 6"},
{"p1" : "1.7238E-16 "} ,{"sumps2" :" 14"},
{"p1" : "1.60135E-15 "} ,{"sumps2" :" 3"},
{"p1" : "119.94E-15 "} ,{"sumps2" :" 2"},
{"p1" : "7.908E-16 "} ,{"sumps2" :" 5"},
{"p1" : "4.463E-16 "} ,{"sumps2" :" 3"},
{"p1" : "6.32095E-15 "} ,{"sumps2" :" 3"},
{"p1" : "7.26269E-15 "} ,{"sumps2" :" 3"},
{"p1" : "1.362E-14 "} ,{"sumps2" :" 2"},
{"p1" : "1.677E-15 "} ,{"sumps2" :" 10"},
{"p1" : "2.334387E-14 "} ,{"sumps2" :" 5"},
{"p1" : "0.00004912E-15 "} ,{"sumps2" :" 12"},
{"p1" : "8.7494E-14 "} ,{"sumps2" :" 8"},
{"p1" : "1.07E-16 "} ,{"sumps2" :" 9"},
{"p1" : "1.887E-15 "} ,{"sumps2" :" 18"},
{"p1" : "4.63E-16 "} ,{"sumps2" :" 6"},
{"p1" : "1.49E-16 "} ,{"sumps2" :" 3"},
{"p1" : "2.489796E-14 "} ,{"sumps2" :" 4"},
{"p1" : "0.5220E-15 "} ,{"sumps2" :" 3"},
{"p1" : "1.8303E-15 "} ,{"sumps2" :" 2"},
{"p1" : "6.695000E-16 "} ,{"sumps2" :" 17"},
{"p1" : "1.5151E-14 "} ,{"sumps2" :" 2"},
{"p1" : "3.33E-16 "} ,{"sumps2" :" 17"},
{"p1" : "3.59E-15 "} ,{"sumps2" :" 5"},
{"p1" : "0.01E-15 "} ,{"sumps2" :" 2"},
{"p1" : "3.60812E-15 "} ,{"sumps2" :" 4"},
{"p1" : "1.37294E-14 "} ,{"sumps2" :" 10"},
{"p1" : "9.7569E-14 "} ,{"sumps2" :" 4"},
{"p1" : "3.5477E-14 "} ,{"sumps2" :" 5"},
{"p1" : "4.878E-15 "} ,{"sumps2" :" 2"},
{"p1" : "2.50E-16 "} ,{"sumps2" :" 15"},
{"p1" : "8.37E-15 "} ,{"sumps2" :" 8"}
]
}
</textarea>
答案 0 :(得分：0)
它是正确的，因为obj2.dataset2 [4]就是这个对象{＆＃34; p1＆＃34; ：＆＃34; 5.6446E-16＆＃34;}
答案 1 :(得分：0)
假设您要做的是获取p1值的最大值并在不使用科学记数法的情况下显示它，这应该适合您。
// Parse data
var data2_JSON = document.getElementById('JSON3').value;
var obj2 = JSON.parse(data2_JSON);
// Find maximum p1
function getMaxY() {
return obj2.dataset2.reduce(function(p, c, i){
// Ignore missing values - Could use (i % 2) here if the order was known to be consistent.
return (typeof(c.p1) === 'undefined') ? p : Math.max(p, parseFloat(c.p1, 10));
}, 0);
}
// var sNum = "1.23e-2";
// alert(parseFloat(sNum));
// alert(parseFloat(obj2.dataset2[4].p1));
// Use toFixed() to ensure the value is not presented with scientific notation
alert(getMaxY().toFixed(20));<textarea id="JSON3">
{"dataset2": [
{"p1" : "2.097E-15 "} ,{"sumps2" :" 12"},
{"p1" : "3.6039E-13 "} ,{"sumps2" :" 5"},
{"p1" : "5.6446E-16 "} ,{"sumps2" :" 14"},
{"p1" : "-4.9850E-20 "} ,{"sumps2" :" 7"},
{"p1" : "4.878E-15 "} ,{"sumps2" :" 2"},
{"p1" : "2.50E-16 "} ,{"sumps2" :" 15"},
{"p1" : "8.37E-15 "} ,{"sumps2" :" 8"}
]}
</textarea>
答案 2 :(得分：0)
最后，我找到了一个不同的解决方案，使Transform函数在画布上呈现宽度和高度变量的数据。
var transx = makeTransform([minlogP0, maxlogP0], [mingraphx, maxgraphx]);
var transy = makeTransform([minlogP1, maxlogP1], [maxgraphy, mingraphy]);
// function to create the needed linear transforms
// note from and to are two element arrays (see below):
function makeTransform(from, to){
// determine a and b in terms of from[0], from[1], to[0] and to[1]
var x1 = from[0];
var x2 = from[1];
var y1 = to[0];
var y2 = to[1];
var a = (y1 - y2) / (x1 - x2);
var b = y1 - a * x1;
return function(x){return a * x + b;};
}