我正在为MPC 555板写C,需要弄清楚如何在不使用malloc的情况下分配动态内存.
你如何控制动画的速度?我的物体在另一台机器上的动画效果更快.
void idle(void){
if (!wantPause){
circleSpin = circleSpin + 2.0; //spin circles
if(circleSpin > 360.0)
{
circleSpin = circleSpin - 360.0;
}
diamondSpin = diamondSpin - 4.0; //spin diamonds
if(diamondSpin > 360.0)
{
diamondSpin = diamondSpin + 360.0;
}
ellipseScale = ellipseScale + 0.1; //scale ellipse
if(ellipseScale > 30)
{
ellipseScale = 15;
}
glutPostRedisplay();
}
}
void drawScene()
{
...
glColor3f(1,0,0);
glPushMatrix();
glRotatef(circleSpin,0,0,1);
drawOuterCircles();
glPopMatrix();
}
int main (int argc, char** argv)
{
glutInit(&argc, argv);
glutInitWindowSize(400,400);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB …Run Code Online (Sandbox Code Playgroud) 如何在不使用C中的sprintf或ftoa的情况下将float/double转换为ASCII?
我正在使用嵌入式系统.
我曾经strtol将字符串转换为十六进制,现在我需要将它打印到屏幕上.我不确定我是否可以使用,sprintf因为我只有20k的内存才能在这块板上使用.备选方案欢迎.
我正在使用以前创建的日期将完整的等待列表注册CSV导入到我的数据库中,如何在保留其初始日期的同时导入它们而不是让它们都显示相同的导入日期?
我收到错误: Rails can't mass-assign protected attributes for id, created_at
代码:
csv_file = params[:csv][:file].read
csv = CSV.parse(csv_file, :headers => false)
csv.each do |row|
Model.create!(:email => row[0], :created_at => row[1])
end
Run Code Online (Sandbox Code Playgroud) 我在同一页面上运行两个javascript文件时遇到问题.我使用了JQuery.noConflict()(http://api.jquery.com/jQuery.noConflict/),但没有运气.
<script src="http://www.google.com/jsapi"></script>
<script>
google.load("prototype", "1.6.0.3",{uncompressed:false});
google.load("scriptaculous", "1.8.1",{uncompressed:false});
</script>
<script src="js/jquery.tools.min.js"></script>
<script type="text/javascript">
$jQuery.noConflict();
jQuery(document).ready(function($) {
$("#download_now").tooltip({ effect: 'slide'});
});
function show_text() {
new Ajax.Request('./new.php', {
method: 'post',
parameters: { userid: $('userid').value },
onSuccess: function(r) { $('update').update(r.responseText) }
});
}
document.observe("dom:loaded", function() {
$('loading').hide();
Ajax.Responders.register({
onCreate: function() {
new Effect.Opacity('loading',{ from: 1.0, to: 0.3, duration: 0.7 });
new Effect.toggle('loading', 'appear');
},
onComplete: function() {
new Effect.Opacity('loading', { from: 0.3, to: 1, duration: 0.7 });
new Effect.toggle('loading', 'appear');
} …Run Code Online (Sandbox Code Playgroud) 我可以使用哪个字符串函数来删除所有内容-?字符串未预定义,因此rtrim()不起作用.
9453 - abcafaf3ceb895d7b1636ad24c37cb9f-100.png?1
在这种情况下,我希望能够返回15号:
Array ( [420315] => 1 [21714] => 1 [20] => 1 [1] => 1 [18] => 1 [241] => 2 [15] => 5 [1038401] => 1 [114] => 1 [293641] => 1 [387] => 1 [232] => 1 [11368] => 1 [9225] => 1 [100] => 1 [9254] => 1 [15326] => 1 [9246] => 1 [97] => 1 [9241] => 1 [14242] => 1 [9456] => 1 [366] => 1 [130] => 1 [373] => 1 )
Run Code Online (Sandbox Code Playgroud) 我有一个如下所示的文件.我想要的只是电压,剥离其他所有东西最简单的方法是什么?
Time,Voltage,Peak
0.0,1.003911558621642,3
0.00390625,1.0327467181982755,0
0.0078125,0.9904463156237306,0
0.01171875,0.6867661682528724,0
0.015625,0.6236803073669519,0
0.01953125,0.2934711210503298,0
0.0234375,0.06148933838536881,0
0.02734375,0.07053968550834916,0
0.03125,-0.09041720958299812,0
0.03515625,-0.28273374252040306,0
0.0390625,-0.29775398016603216,0
Run Code Online (Sandbox Code Playgroud)