R语言入门：vegan包diversity()、simpson.unb()、fisher.alpha()、specnumber函数

frameworks/base/services/core/java/com/android/server/timezonedetector/TimeZoneDetectorCallbackImpl.java

    public boolean isDeviceTimeZoneInitialized() {
        // timezone.equals("GMT") will be true and only true if the time zone was
        // set to a default value by the system server (when starting, system server
        // sets the persist.sys.timezone to "GMT" if it's not set). "GMT" is not used by
        // any code that sets it explicitly (in case where something sets GMT explicitly,
        // "Etc/GMT" Olson ID would be used).

        String timeZoneId = getDeviceTimeZone();
        return timeZoneId != null && timeZoneId.length() > 0 && !timeZoneId.equals("GMT");
    }

    @Override
    @Nullable
    public String getDeviceTimeZone() {
        return SystemProperties.get(TIMEZONE_PROPERTY);
    }


private static final String TIMEZONE_PROPERTY = "persist.sys.timezone";

private static final String TIMEZONE_PROPERTY = "persist.sys.timezone";

这个是设置时区的属性 persist.sys.timezone

在android源码目录 build/make/core/main.mk

添加默认 persist.sys.timezone默认属性